Statistics
By the end of this chapter you will be able to
- Read the numbers in a table, and find totals using the row and column headings
- Read a pictogram by using its key, including a half picture
- Read a scaled bar chart, where one square stands for 2 or 5 units
- Count tally marks, and present data as a table, a pictogram or a bar chart
- Answer one-step questions: how many more and how many fewer
- Answer two-step questions, and check each step
You should already know
- Tally charts and simple tables of data (Year 2, Chapter 10)
- Adding and subtracting numbers with up to 3 digits (Year 3, Chapter 2)
- Multiplication facts for the 3, 4 and 8 times tables (Year 3, Chapter 3)
Where this leads
- Reading bar charts and simple tables with bigger numbers, and comparing data (Year 4, Chapter 11)
- Reading line graphs and timetables (Year 5, Chapter 11)
National Curriculum for England, Key Stage 2 mathematics, Year 3. Content: Interpret and present data using bar charts, pictograms and tables, Solve one-step and two-step questions (for example, "How many more?" and "How many fewer?") using information presented in scaled bar charts, pictograms and tables.
Exercise P Do you remember?
Non-calculatorMethod. Add the ones first, then the tens, then the hundreds. Carry a ten or a hundred when needed.
- Add the ones. Write 3 in the ones place. Carry 1 ten.4 + 9 = 13
- Add the tens, with the ten we carried. Write the tens digit of the answer.1 + 7 + 1 = 9
- Add the hundreds. Add the hundreds digits and any hundred we carried.2 + 3 + 0 = 5
- Write the answer. Put the hundreds, tens and ones together.593
Check. 593 − 379 = 214. ✓
Watch out. Start with the ones. Do not add the hundreds first.
Method. Count on in two jumps, then add the jumps together.
- Count on from 268 to 300. It is 32 to get to 300.268 + 32 = 300
- Count on from 300 to the bigger number. It is 200 more.300 + 200 = 500
- Add the two jumps. The total of the two jumps is the difference.32 + 200 = 232
- Write the answer. 232
Check. 268 + 232 = 500. ✓
Watch out. Do not subtract the digits one at a time when you are counting on.
Method. Add 4 to itself 6 times.
- Write the groups. We have 6 groups of 4.6 × 4
- Add the groups together. Add 4, 6 times.4 + 4 + 4 + 4 + 4 + 4 = 24
- Write the answer. 24
Check. 4 × 6 = 24 as well. ✓
Watch out. Count the groups, not the numbers in them.
Key words. A tally counts in groups of five. Four upright marks and one line across them make a group of five.
Method. Count the groups of five, then count the single marks and add them.
- Look at the tally marks. Count the groups of five first.1 group of five and 2 single marks
- Count the marks in the groups. Each group of five has five marks.1 × 5 = 5
- Add the single marks. Add the marks that are not in a group.5 + 2 = 7
- Write the answer. The answer is the total number of marks.7
Check. Counting the marks one at a time also gives 7. ✓
Watch out. A group of five has four upright marks and one line across them. Count each group as five.
Method. Add 8 to itself 4 times.
- Write the groups. We have 4 groups of 8.4 × 8
- Add the groups together. Add 8, 4 times.8 + 8 + 8 + 8 = 32
- Write the answer. 32
Check. 8 × 4 = 32 as well. ✓
Watch out. Count the groups, not the numbers in them.
Reading a table
A table puts information into rows and columns. The words across the top are the column headings. The words down the left side are the row headings.
To find a number, put your finger on the row heading, and slide it across the row. Then look up at the column heading. The number where the row and the column meet is the answer.
Some tables have more than one row, such as boys and girls. Read the row for the group you want, and the column for the day or the lunch you want.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key ideas
- A table has rows across the page and columns down the page.
- The row headings are on the left. The column headings are at the top.
- Read the number where the row and the column meet.
- To find a total, add the numbers in a row, or in a column.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Children.Column: Children
- Find the row heading. Look down the left-hand side for Pasta.Row: Pasta
- Read the number where they meet. Read across the row and down the column until they meet.Pasta, Children = 6
- Write the answer. Write the number only.6
Check. 6 is the number in the Pasta row under Children. ✓
Watch out. Read across the row, not down the column next to it.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Wednesday.Column: Wednesday
- Find the row heading. Look down the left-hand side for Boys.Row: Boys
- Read the number where they meet. Read across the row and down the column until they meet.Boys, Wednesday = 4
- Write the answer. Write the number only.4
Check. 4 is the number in the Boys row under Wednesday. ✓
Watch out. Read across the row, not down the column next to it.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Method. Read each number, then add them together to find the total.
- Read the number for the boys on Thursday. Read it from the table, chart or list.the boys on Thursday = 6
- Read the number for the girls on Thursday. Read it from the table, chart or list.the girls on Thursday = 4
- Add the numbers together. Add every number to find the total.6 + 4 = 10
- Write the answer. The total is the answer.10
Check. 10 − 4 = 6, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Watch out
Watch out: read the number where the row and the column meet. A number next to a row heading is not always in the column you want, so check the column heading again before you write the answer.
Exam tip
Grown-up tip. Ask your child to put one finger on a row heading and one on a column heading, then move them until they meet. Ask: "Which row are we in? Which column?" Check the answer together.
Exercise 9A Reading numbers in tables
Non-calculatorFavourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Children.Column: Children
- Find the row heading. Look down the left-hand side for Wraps.Row: Wraps
- Read the number where they meet. Read across the row and down the column until they meet.Wraps, Children = 7
- Write the answer. Write the number only.7
Check. 7 is the number in the Wraps row under Children. ✓
Watch out. Read across the row, not down the column next to it.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Children.Column: Children
- Find the row heading. Look down the left-hand side for Jacket potato.Row: Jacket potato
- Read the number where they meet. Read across the row and down the column until they meet.Jacket potato, Children = 4
- Write the answer. Write the number only.4
Check. 4 is the number in the Jacket potato row under Children. ✓
Watch out. Read across the row, not down the column next to it.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Method. Read the number for each lunch, then add them together to find the class total.
- Read the number for Pizza. Read it from the table, chart or list.Pizza = 9
- Read the number for Pasta. Read it from the table, chart or list.Pasta = 6
- Read the number for Jacket potato. Read it from the table, chart or list.Jacket potato = 4
- Read the number for Wraps. Read it from the table, chart or list.Wraps = 7
- Add the numbers together. Add every number to find the total.9 + 6 + 4 + 7 = 26
- Write the answer. The total is the answer.26
Check. 26 − 7 = 19, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Wednesday.Column: Wednesday
- Find the row heading. Look down the left-hand side for Girls.Row: Girls
- Read the number where they meet. Read across the row and down the column until they meet.Girls, Wednesday = 7
- Write the answer. Write the number only.7
Check. 7 is the number in the Girls row under Wednesday. ✓
Watch out. Read across the row, not down the column next to it.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Friday.Column: Friday
- Find the row heading. Look down the left-hand side for Boys.Row: Boys
- Read the number where they meet. Read across the row and down the column until they meet.Boys, Friday = 8
- Write the answer. Write the number only.8
Check. 8 is the number in the Boys row under Friday. ✓
Watch out. Read across the row, not down the column next to it.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Method. Read each number, then add them together to find the total.
- Read the number for the boys on Tuesday. Read it from the table, chart or list.the boys on Tuesday = 7
- Read the number for the girls on Tuesday. Read it from the table, chart or list.the girls on Tuesday = 5
- Add the numbers together. Add every number to find the total.7 + 5 = 12
- Write the answer. The total is the answer.12
Check. 12 − 5 = 7, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Monday.Column: Monday
- Find the row heading. Look down the left-hand side for Girls.Row: Girls
- Read the number where they meet. Read across the row and down the column until they meet.Girls, Monday = 6
- Write the answer. Write the number only.6
Check. 6 is the number in the Girls row under Monday. ✓
Watch out. Read across the row, not down the column next to it.
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Tuesday.Column: Tuesday
- Find the row heading. Look down the left-hand side for Boys.Row: Boys
- Read the number where they meet. Read across the row and down the column until they meet.Boys, Tuesday = 7
- Write the answer. Write the number only.7
Check. 7 is the number in the Boys row under Tuesday. ✓
Watch out. Read across the row, not down the column next to it.
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Friday.Column: Friday
- Find the row heading. Look down the left-hand side for Girls.Row: Girls
- Read the number where they meet. Read across the row and down the column until they meet.Girls, Friday = 6
- Write the answer. Write the number only.6
Check. 6 is the number in the Girls row under Friday. ✓
Watch out. Read across the row, not down the column next to it.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the total for each day by adding the boys and girls, then choose the biggest total.
- Add the boys and the girls on Monday. Add the two numbers in that column.5 + 6 = 11
- Add the boys and the girls on Tuesday. Add the two numbers in that column.7 + 5 = 12
- Add the boys and the girls on Wednesday. Add the two numbers in that column.4 + 7 = 11
- Add the boys and the girls on Thursday. Add the two numbers in that column.6 + 4 = 10
- Add the boys and the girls on Friday. Add the two numbers in that column.8 + 6 = 14
- Find the biggest total. Friday has the biggest total, 14.biggest = 14
- Write the answer. Write the day with the biggest total.Friday
Check. 14 is bigger than every other day total. ✓
Watch out. Add the boys and the girls first. Do not compare only the boys or only the girls.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Method. Find the total for Monday and the total for Friday, then add them together.
- Read the number for the boys on Monday. Read it from the table, chart or list.the boys on Monday = 5
- Read the number for the girls on Monday. Read it from the table, chart or list.the girls on Monday = 6
- Read the number for the boys on Friday. Read it from the table, chart or list.the boys on Friday = 8
- Read the number for the girls on Friday. Read it from the table, chart or list.the girls on Friday = 6
- Add the numbers together. Add every number to find the total.5 + 6 + 8 + 6 = 25
- Write the answer. The total is the answer.25
Check. 25 − 6 = 19, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Take the number of girls away from the total for Monday. The rest are boys.
- Write the total for Monday. The table gives the total for the whole day.11 children
- Write the number of girls. The girls are part of the total.6 girls
- Take the girls away from the total. What is left must be the boys.11 − 6 = 5
- Write the answer. This is the number of boys on Monday.5
Check. 5 boys and 6 girls make 11 children. ✓
Watch out. Use the total you are given. Do not add the girls to the total.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the total number of boys and the total number of girls, then compare them.
- Find the total number of boys. Add the boys for every day.5 + 7 + 4 + 6 + 8 = 30
- Find the total number of girls. Add the girls for every day.6 + 5 + 7 + 4 + 6 = 28
- Compare the two totals. 30 is more than 28, so more boys came altogether.30 > 28
- Decide. Sam said more girls came, which is not true.No
Check. 28 + 2 = 30, so the boys had 2 more. ✓
Watch out. Add all five days for each group. Do not compare only one day.
Reading a pictogram
A pictogram shows numbers with pictures. Every picture stands for the same number. The key tells you how many one picture stands for.
To find the number for one row, count the whole pictures and multiply by the key. For example, if the key is 2 and there are 4 whole pictures, the number is 4 × 2 = 8.
Sometimes a row ends with a half picture. With a key of 2, a half picture stands for 1, so you add 1 to the whole pictures.
Key ideas
- Read the key first. It tells you what one picture stands for.
- Count the whole pictures, then multiply the number of pictures by the key.
- A half picture is half of the key. With a key of 2, a half picture stands for 1.
- Check your answer: the whole pictures times the key, plus any half picture, must give the number.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Hamsters. Read along the row to see all of its pictures.Row: Hamsters
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.2 × 2 = 4
- Write the answer. The whole pictures make the whole number.4
Check. 2 × 2 = 4. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Fish. Read along the row to see all of its pictures.Row: Fish
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.1 × 2 = 2
- Count the half picture. A half picture is half of the key, so it stands for 1.half picture = 1
- Add the half picture. Add it to the whole pictures.2 + 1 = 3
Check. 1 × 2 + 1 = 3. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Tuesday. Read along the row to see all of its pictures.Row: Tuesday
- Count the whole pictures and multiply by the key. Each whole picture stands for 5 books.4 × 5 = 20
- Write the answer. The whole pictures make the whole number.20
Check. 4 × 5 = 20. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Watch out
Watch out: do not write the number of pictures as the answer. Four pictures with a key of 5 stand for 20 books, not 4.
Exam tip
Grown-up tip. Ask your child to point to each picture and count out loud, then ask: "How many does one picture stand for? So what is the total for the row?" For a half picture, ask: "What is half of the key?"
Exercise 9B Reading pictograms with a key
Non-calculatorKey words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Dogs. Read along the row to see all of its pictures.Row: Dogs
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.5 × 2 = 10
- Write the answer. The whole pictures make the whole number.10
Check. 5 × 2 = 10. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Cats. Read along the row to see all of its pictures.Row: Cats
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.3 × 2 = 6
- Count the half picture. A half picture is half of the key, so it stands for 1.half picture = 1
- Add the half picture. Add it to the whole pictures.6 + 1 = 7
Check. 3 × 2 + 1 = 7. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Hamsters. Read along the row to see all of its pictures.Row: Hamsters
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.2 × 2 = 4
- Write the answer. The whole pictures make the whole number.4
Check. 2 × 2 = 4. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Fish. Read along the row to see all of its pictures.Row: Fish
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.1 × 2 = 2
- Count the half picture. A half picture is half of the key, so it stands for 1.half picture = 1
- Add the half picture. Add it to the whole pictures.2 + 1 = 3
Check. 1 × 2 + 1 = 3. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Method. Work out the number for each row of the pictogram, then add them together.
- Read the number for Dogs. Read it from the table, chart or list.Dogs = 10
- Read the number for Cats. Read it from the table, chart or list.Cats = 7
- Read the number for Hamsters. Read it from the table, chart or list.Hamsters = 4
- Read the number for Fish. Read it from the table, chart or list.Fish = 3
- Add the numbers together. Add every number to find the total.10 + 7 + 4 + 3 = 24
- Write the answer. The total is the answer.24
Check. 24 − 3 = 21, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Thursday. Read along the row to see all of its pictures.Row: Thursday
- Count the whole pictures and multiply by the key. Each whole picture stands for 5 books.6 × 5 = 30
- Write the answer. The whole pictures make the whole number.30
Check. 6 × 5 = 30. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Monday. Read along the row to see all of its pictures.Row: Monday
- Count the whole pictures and multiply by the key. Each whole picture stands for 5 books.3 × 5 = 15
- Write the answer. The whole pictures make the whole number.15
Check. 3 × 5 = 15. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Class 3C. Read along the row to see all of its pictures.Row: Class 3C
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.7 × 2 = 14
- Count the half picture. A half picture is half of the key, so it stands for 1.half picture = 1
- Add the half picture. Add it to the whole pictures.14 + 1 = 15
Check. 7 × 2 + 1 = 15. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Class 3D. Read along the row to see all of its pictures.Row: Class 3D
- Count the whole pictures and multiply by the key. Each whole picture stands for 2 children.2 × 2 = 4
- Count the half picture. A half picture is half of the key, so it stands for 1.half picture = 1
- Add the half picture. Add it to the whole pictures.4 + 1 = 5
Check. 2 × 2 + 1 = 5. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Read every number, then find the most one.
- Read the number for Monday. Read it from the chart.Monday = 15
- Read the number for Tuesday. Read it from the chart.Tuesday = 20
- Read the number for Wednesday. Read it from the chart.Wednesday = 5
- Read the number for Thursday. Read it from the chart.Thursday = 30
- Read the number for Friday. Read it from the chart.Friday = 10
- Find the biggest number. The most is the biggest number.biggest = 30
- Write the answer. Write the name with the number.Thursday
Check. 30 is bigger than all the other numbers. ✓
Watch out. Read every bar or picture row before you choose. Check the key first.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the pictures in the Wednesday row, then multiply by the key. Compare the answer with what Tom said.
- Count the pictures in the Wednesday row. There is one picture in the row.1 picture
- Multiply by the key. Each picture stands for 5 books.1 × 5 = 5
- Compare with what Tom said. Tom said 10 books, but the row shows 5 books.5 is not 10
- Decide. So Tom is not right.No
Check. Two pictures would be 10 books, but there is only one picture, so 5 books. ✓
Watch out. Count the pictures in the row, then use the key. Do not use the number of pictures on another row.
Reading a scaled bar chart
A bar chart uses bars to show numbers. The longer the bar, the bigger the number.
In a scaled bar chart, one square stands for more than one. Look at the key first, to see how much each square stands for.
To find the number for a bar, count the squares up to the top of the bar. Then multiply the number of squares by the key. The numbers along the side are the values of the lines, so you can use them to check your count.
Key ideas
- Read the key first. It says how much each square stands for.
- Count the squares up to the top of each bar.
- Multiply the number of squares by the key to find the number.
- Use the numbers on the scale to check your answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Hawks. Find the label under the bar.Bar: Hawks
- Count the squares up to the top of the bar. Each square stands for 2 goals.7 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.7 × 2 = 14
- Write the answer. This is the number of goals.14
Check. 7 squares of 2 make 14. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Class 3C. Find the label under the bar.Bar: Class 3C
- Count the squares up to the top of the bar. Each square stands for 5 bottles.3 squares
- Multiply the squares by the scale. Each square is worth 5, so multiply the squares by 5.3 × 5 = 15
- Write the answer. This is the number of bottles.15
Check. 3 squares of 5 make 15. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Team A. Find the label under the bar.Bar: Team A
- Count the squares up to the top of the bar. Each square stands for 5 points.7 squares
- Multiply the squares by the scale. Each square is worth 5, so multiply the squares by 5.7 × 5 = 35
- Write the answer. This is the number of points.35
Check. 7 squares of 5 make 35. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Watch out
Watch out: a square is not always worth one. If one square stands for 5 bottles, then 3 squares are 15 bottles, not 3 bottles.
Exam tip
Grown-up tip. Ask your child to read the key out loud, then count the squares for one bar with a finger. Ask: "How many does one square stand for? So how many is the bar?"
Exercise 9C Reading scaled bar charts
Non-calculatorKey words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Eagles. Find the label under the bar.Bar: Eagles
- Count the squares up to the top of the bar. Each square stands for 2 goals.4 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.4 × 2 = 8
- Write the answer. This is the number of goals.8
Check. 4 squares of 2 make 8. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Owls. Find the label under the bar.Bar: Owls
- Count the squares up to the top of the bar. Each square stands for 2 goals.3 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.3 × 2 = 6
- Write the answer. This is the number of goals.6
Check. 3 squares of 2 make 6. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Falcons. Find the label under the bar.Bar: Falcons
- Count the squares up to the top of the bar. Each square stands for 2 goals.5 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.5 × 2 = 10
- Write the answer. This is the number of goals.10
Check. 5 squares of 2 make 10. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Class 3A. Find the label under the bar.Bar: Class 3A
- Count the squares up to the top of the bar. Each square stands for 5 bottles.5 squares
- Multiply the squares by the scale. Each square is worth 5, so multiply the squares by 5.5 × 5 = 25
- Write the answer. This is the number of bottles.25
Check. 5 squares of 5 make 25. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Class 3D. Find the label under the bar.Bar: Class 3D
- Count the squares up to the top of the bar. Each square stands for 5 bottles.6 squares
- Multiply the squares by the scale. Each square is worth 5, so multiply the squares by 5.6 × 5 = 30
- Write the answer. This is the number of bottles.30
Check. 6 squares of 5 make 30. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Bea. Find the label under the bar.Bar: Bea
- Count the squares up to the top of the bar. Each square stands for 2 books.8 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.8 × 2 = 16
- Write the answer. This is the number of books.16
Check. 8 squares of 2 make 16. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Eva. Find the label under the bar.Bar: Eva
- Count the squares up to the top of the bar. Each square stands for 2 books.2 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.2 × 2 = 4
- Write the answer. This is the number of books.4
Check. 2 squares of 2 make 4. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Read every number, then find the fewest one.
- Read the number for Ali. Read it from the chart.Ali = 12
- Read the number for Bea. Read it from the chart.Bea = 16
- Read the number for Cal. Read it from the chart.Cal = 6
- Read the number for Dev. Read it from the chart.Dev = 10
- Read the number for Eva. Read it from the chart.Eva = 4
- Find the smallest number. The fewest is the smallest number.smallest = 4
- Write the answer. Write the name with the number.Eva
Check. 4 is smaller than all the other numbers. ✓
Watch out. Read every bar or picture row before you choose. Check the key first.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Team B. Find the label under the bar.Bar: Team B
- Count the squares up to the top of the bar. Each square stands for 5 points.4 squares
- Multiply the squares by the scale. Each square is worth 5, so multiply the squares by 5.4 × 5 = 20
- Write the answer. This is the number of points.20
Check. 4 squares of 5 make 20. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Read every number, then find the most one.
- Read the number for Team A. Read it from the chart.Team A = 35
- Read the number for Team B. Read it from the chart.Team B = 20
- Read the number for Team C. Read it from the chart.Team C = 45
- Find the biggest number. The most is the biggest number.biggest = 45
- Write the answer. Write the name with the number.Team C
Check. 45 is bigger than all the other numbers. ✓
Watch out. Read every bar or picture row before you choose. Check the key first.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares on the Team C bar, then multiply by the key. Compare the answer with what Ali said.
- Count the squares on the Team C bar. Count the squares up to the top of the bar.9 squares
- Multiply the squares by the key. Each square stands for 5 points.9 × 5 = 45
- Compare with what Ali said. Ali said Team C scored 45 points.45 = 45
- Decide. The bar shows 45 points, so Ali is right.Yes
Check. 9 squares of 5 points make 45 points. ✓
Watch out. Count the squares, then multiply by the key. The bar is not the same as the number of squares.
Presenting data
To present data means to organise it, so that other people can read it quickly.
First, count each choice. A tally counts in groups of five: four upright marks and one line across them make a group of five. Count the groups first, then the single marks left over.
Next, write each total in a table. To draw a pictogram, divide the total by the key. To draw a bar chart, divide the total by the scale. The answer tells you how many whole pictures, or squares, to draw.
Key ideas
- Use a tally to count each choice.
- Write the total for each choice in a table.
- Number of pictures = total ÷ key.
- Number of squares = total ÷ scale.
Key words. A tally counts in groups of five. Four upright marks and one line across them make a group of five.
Method. Count the groups of five, then count the single marks and add them.
- Look at the tally marks for Yellow. Count the groups of five first.1 group of five and 1 single mark
- Count the marks in the groups. Each group of five has five marks.1 × 5 = 5
- Add the single marks. Add the marks that are not in a group.5 + 1 = 6
- Write the answer. The answer is the total number of marks.6
Check. Counting the marks one at a time also gives 6. ✓
Watch out. A group of five has four upright marks and one line across them. Count each group as five.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide the total by what one square stands for.
- Write the total. We need to show 18 goals.18 goals
- Divide by how many one square stands for. One square stands for 2 goals.18 ÷ 2 = 9
- Write the number of squares. 9 whole squares.9
Check. 9 × 2 = 18. ✓
Watch out. Divide, do not multiply. A bigger number of goals needs more squares.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Divide the total by what one picture stands for.
- Write the total. We need to show 20 children.20 children
- Divide by how many one picture stands for. One picture stands for 5 children.20 ÷ 5 = 4
- Write the number of pictures. 4 whole pictures.4
Check. 4 × 5 = 20. ✓
Watch out. Divide, do not multiply. A bigger number of children needs more pictures.
Watch out
Watch out: divide the total by the key or the scale. Do not multiply. A bar for 18 goals, with one square for 2 goals, is 9 squares tall, not 36.
Exam tip
Grown-up tip. Ask your child to make a tally for a few things in the house, such as the socks in a drawer, then write the totals in a small table. Ask: "How many pictures would we need if one picture stood for 2 socks?"
Exercise 9D Counting, tallies and drawing charts
Non-calculatorKey words. A tally counts in groups of five. Four upright marks and one line across them make a group of five.
Method. Count the groups of five, then count the single marks and add them.
- Look at the tally marks for Blue. There are no full groups of five.4 marks altogether
- Count the marks. Count each single mark.4 marks
- Write the answer. The answer is the number of marks.4
Check. Counting the marks one at a time also gives 4. ✓
Watch out. A group of five has four upright marks and one line across them. Count each group as five.
Key words. A tally counts in groups of five. Four upright marks and one line across them make a group of five.
Method. Count the groups of five, then count the single marks and add them.
- Look at the tally marks for Red. Count the groups of five first.1 group of five and 2 single marks
- Count the marks in the groups. Each group of five has five marks.1 × 5 = 5
- Add the single marks. Add the marks that are not in a group.5 + 2 = 7
- Write the answer. The answer is the total number of marks.7
Check. Counting the marks one at a time also gives 7. ✓
Watch out. A group of five has four upright marks and one line across them. Count each group as five.
Method. Count the votes for each colour, then add them together.
- Read the number for Red. Read it from the table, chart or list.Red = 7
- Read the number for Blue. Read it from the table, chart or list.Blue = 4
- Read the number for Yellow. Read it from the table, chart or list.Yellow = 6
- Read the number for Green. Read it from the table, chart or list.Green = 3
- Add the numbers together. Add every number to find the total.7 + 4 + 6 + 3 = 20
- Write the answer. The total is the answer.20
Check. 20 − 3 = 17, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
The class wrote down the favourite fruit of each child. Each word is one child: apple, banana, pear, apple, orange, banana, apple, pear, banana, apple, apple, orange, pear, banana, apple, orange, banana, pear, apple, banana.
Key words. Data is information that we collect and count, such as the number of children who chose each pet.
Method. Go through the list and count each apple.
- Read the list. Each word is one child.20 words in the list
- Count the words that say apple. Go through the list and count each one.apple = 7
- Write the answer. The answer is the number of times the word appears.7
Check. The other 13 words are not apple, and 7 + 13 = 20. ✓
Watch out. Count every word, even when the same word is in the list many times.
The class wrote down the favourite fruit of each child. Each word is one child: apple, banana, pear, apple, orange, banana, apple, pear, banana, apple, apple, orange, pear, banana, apple, orange, banana, pear, apple, banana.
Key words. Data is information that we collect and count, such as the number of children who chose each pet.
Method. Go through the list and count each banana.
- Read the list. Each word is one child.20 words in the list
- Count the words that say banana. Go through the list and count each one.banana = 6
- Write the answer. The answer is the number of times the word appears.6
Check. The other 14 words are not banana, and 6 + 14 = 20. ✓
Watch out. Count every word, even when the same word is in the list many times.
The class wrote down the favourite fruit of each child. Each word is one child: apple, banana, pear, apple, orange, banana, apple, pear, banana, apple, apple, orange, pear, banana, apple, orange, banana, pear, apple, banana.
Key words. Data is information that we collect and count, such as the number of children who chose each pet.
Method. Go through the list and count each pear.
- Read the list. Each word is one child.20 words in the list
- Count the words that say pear. Go through the list and count each one.pear = 4
- Write the answer. The answer is the number of times the word appears.4
Check. The other 16 words are not pear, and 4 + 16 = 20. ✓
Watch out. Count every word, even when the same word is in the list many times.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Divide the total by what one picture stands for.
- Write the total. We need to show 14 children.14 children
- Divide by how many one picture stands for. One picture stands for 2 children.14 ÷ 2 = 7
- Write the number of pictures. 7 whole pictures.7
Check. 7 × 2 = 14. ✓
Watch out. Divide, do not multiply. A bigger number of children needs more pictures.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide the total by what one square stands for.
- Write the total. We need to show 25 books.25 books
- Divide by how many one square stands for. One square stands for 5 books.25 ÷ 5 = 5
- Write the number of squares. 5 whole squares.5
Check. 5 × 5 = 25. ✓
Watch out. Divide, do not multiply. A bigger number of books needs more squares.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide the total by what one square stands for.
- Write the total. We need to show 24 goals.24 goals
- Divide by how many one square stands for. One square stands for 2 goals.24 ÷ 2 = 12
- Write the number of squares. 12 whole squares.12
Check. 12 × 2 = 24. ✓
Watch out. Divide, do not multiply. A bigger number of goals needs more squares.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Divide the total by what one picture stands for.
- Write the total. We need to show 15 children.15 children
- Divide by how many one picture stands for. One picture stands for 2 children.15 ÷ 2 = 7 remainder 1
- Write the number of pictures. 7 whole pictures and one half.7 and a half
Check. 7 × 2 + 1 = 15. ✓
Watch out. Divide, do not multiply. A bigger number of children needs more pictures.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide 9 by 2 to find the number of whole squares, then look at what is left over.
- Divide 9 by 2. Divide the total by the scale.9 ÷ 2 = 4 remainder 1
- Look at the remainder. A remainder of 1 means half a square is left over. Whole squares cannot show it exactly.1 left over = half a square
- Decide. So a bar for 9 goals cannot be drawn exactly with whole squares. Ali is not right.No
Check. 4 × 2 = 8, and 8 + 1 = 9, so one half square is needed. ✓
Watch out. Check the remainder. An odd number needs a half square when the scale is 2.
One-step questions: how many more and how many fewer
A one-step question needs one calculation. The words how many more and how many fewer both ask for the difference between two numbers.
First, find the two numbers. Then subtract the smaller number from the bigger number. Use the key or the scale to find each number first, if the chart uses one.
Key ideas
- A one-step question needs one calculation.
- “How many more” and “how many fewer” both ask for the difference.
- Subtract the smaller number from the bigger number.
- Check: the smaller number plus the difference must give the bigger number.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Dogs. The number for Dogs is 10 children.Dogs = 10
- Find the number for Cats. The number for Cats is 7 children.Cats = 7
- Subtract the smaller number from the bigger number. 10 is more than 7, so take 7 away from 10.10 − 7 = 3
- Write the answer. The difference is 3 children.3
Check. 7 + 3 = 10. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Monday. The number for Monday is 15 books.Monday = 15
- Find the number for Wednesday. The number for Wednesday is 5 books.Wednesday = 5
- Subtract the smaller number from the bigger number. 15 is more than 5, so take 5 away from 15.15 − 5 = 10
- Write the answer. The difference is 10 books.10
Check. 5 + 10 = 15. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Bea. The number for Bea is 16 books.Bea = 16
- Find the number for Dev. The number for Dev is 10 books.Dev = 10
- Subtract the smaller number from the bigger number. 16 is more than 10, so take 10 away from 16.16 − 10 = 6
- Write the answer. The difference is 6 books.6
Check. 10 + 6 = 16. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Watch out
Watch out: subtract the smaller number from the bigger number. Do not start with the smaller number, or you will get a negative answer.
Exam tip
Grown-up tip. Ask your child to read both numbers out loud first, then ask: "Which one is bigger? How much bigger is it?" Count the difference on fingers if that helps.
Exercise 9E How many more and how many fewer
Non-calculatorKey words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Dogs. The number for Dogs is 10 children.Dogs = 10
- Find the number for Hamsters. The number for Hamsters is 4 children.Hamsters = 4
- Subtract the smaller number from the bigger number. 10 is more than 4, so take 4 away from 10.10 − 4 = 6
- Write the answer. The difference is 6 children.6
Check. 4 + 6 = 10. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Cats. The number for Cats is 7 children.Cats = 7
- Find the number for Fish. The number for Fish is 3 children.Fish = 3
- Subtract the smaller number from the bigger number. 7 is more than 3, so take 3 away from 7.7 − 3 = 4
- Write the answer. The difference is 4 children.4
Check. 3 + 4 = 7. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Friday. The number for Friday is 10 books.Friday = 10
- Find the number for Wednesday. The number for Wednesday is 5 books.Wednesday = 5
- Subtract the smaller number from the bigger number. 10 is more than 5, so take 5 away from 10.10 − 5 = 5
- Write the answer. The difference is 5 books.5
Check. 5 + 5 = 10. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Pizza. The number for Pizza is 9 children.Pizza = 9
- Find the number for Wraps. The number for Wraps is 7 children.Wraps = 7
- Subtract the smaller number from the bigger number. 9 is more than 7, so take 7 away from 9.9 − 7 = 2
- Write the answer. The difference is 2 children.2
Check. 7 + 2 = 9. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Pizza. The number for Pizza is 9 children.Pizza = 9
- Find the number for Jacket potato. The number for Jacket potato is 4 children.Jacket potato = 4
- Subtract the smaller number from the bigger number. 9 is more than 4, so take 4 away from 9.9 − 4 = 5
- Write the answer. The difference is 5 children.5
Check. 4 + 5 = 9. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for the boys on Friday. The number for the boys on Friday is 8 children.the boys on Friday = 8
- Find the number for the girls on Friday. The number for the girls on Friday is 6 children.the girls on Friday = 6
- Subtract the smaller number from the bigger number. 8 is more than 6, so take 6 away from 8.8 − 6 = 2
- Write the answer. The difference is 2 children.2
Check. 6 + 2 = 8. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Bea. The number for Bea is 16 books.Bea = 16
- Find the number for Ali. The number for Ali is 12 books.Ali = 12
- Subtract the smaller number from the bigger number. 16 is more than 12, so take 12 away from 16.16 − 12 = 4
- Write the answer. The difference is 4 books.4
Check. 12 + 4 = 16. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Class 3B. The number for Class 3B is 40 bottles.Class 3B = 40
- Find the number for Class 3C. The number for Class 3C is 15 bottles.Class 3C = 15
- Subtract the smaller number from the bigger number. 40 is more than 15, so take 15 away from 40.40 − 15 = 25
- Write the answer. The difference is 25 bottles.25
Check. 15 + 25 = 40. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Class 3C. The number for Class 3C is 15 children.Class 3C = 15
- Find the number for Class 3D. The number for Class 3D is 5 children.Class 3D = 5
- Subtract the smaller number from the bigger number. 15 is more than 5, so take 5 away from 15.15 − 5 = 10
- Write the answer. The difference is 10 children.10
Check. 5 + 10 = 15. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Eagles. The number for Eagles is 8 goals.Eagles = 8
- Find the number for Owls. The number for Owls is 6 goals.Owls = 6
- Subtract the smaller number from the bigger number. 8 is more than 6, so take 6 away from 8.8 − 6 = 2
- Write the answer. The difference is 2 goals.2
Check. 6 + 2 = 8. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Thursday. The number for Thursday is 30 books.Thursday = 30
- Find the number for Tuesday. The number for Tuesday is 20 books.Tuesday = 20
- Subtract the smaller number from the bigger number. 30 is more than 20, so take 20 away from 30.30 − 20 = 10
- Write the answer. The difference is 10 books.10
Check. 20 + 10 = 30. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Two-step questions
A two-step question has two calculations. Do the first step, then use its answer in the second step.
Write down the answer to each step as you go, so that you can check it. Read the whole question, too. Some questions ask for two answers.
Key ideas
- A two-step question needs two calculations.
- Do the first step, then use its answer in the second step.
- Write down the answer to each step.
- Check that the answer makes sense: the total is bigger than each number you added.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. A two-step question needs two calculations. Use the answer from the first step in the second step.
Method. Do the first step, then use its answer in the second step.
- Step 1: read the number for Jacket potato. Read it from the chart or table.Jacket potato = 4
- Step 1: read the number for Wraps. Read it from the chart or table.Wraps = 7
- Step 1: add the numbers together. This is the total for Jacket potato and Wraps.4 + 7 = 11
- Step 2: read the number for Pasta. This is the number to compare with.Pasta = 6
- Step 2: subtract the smaller number from the bigger number. The total of 11 is more than 6, so take 6 away from 11.11 − 6 = 5
- Write the answer. Both answers are needed: 11 children altogether, and 5 children more.5
Check. 6 + 5 = 11. ✓
Watch out. Check that both steps are done. Many answers stop after the first step.
Key words. A two-step question needs two calculations. Use the answer from the first step in the second step.
Method. Do the first step, then use its answer in the second step.
- Step 1: read the number for Tuesday. Read it from the chart or table.Tuesday = 20
- Step 1: read the number for Wednesday. Read it from the chart or table.Wednesday = 5
- Step 1: add the numbers together. This is the total for Tuesday and Wednesday.20 + 5 = 25
- Step 2: read the number for Monday. This is the number to compare with.Monday = 15
- Step 2: subtract the smaller number from the bigger number. The total of 25 is more than 15, so take 15 away from 25.25 − 15 = 10
- Write the answer. Both answers are needed: 25 books altogether, and 10 books more.10
Check. 15 + 10 = 25. ✓
Watch out. Check that both steps are done. Many answers stop after the first step.
Key words. A two-step question needs two calculations. Use the answer from the first step in the second step.
Method. Do the first step, then use its answer in the second step.
- Step 1: read the number for dogs. Read it from the chart or table.dogs = 10
- Step 1: read the number for fish. Read it from the chart or table.fish = 3
- Step 1: add the numbers together. This is the total for dogs and fish.10 + 3 = 13
- Step 2: read the number for hamsters. This is the number to compare with.hamsters = 4
- Step 2: subtract the smaller number from the bigger number. The total of 13 is more than 4, so take 4 away from 13.13 − 4 = 9
- Write the answer. Both answers are needed: 13 children altogether, and 9 children more.9
Check. 4 + 9 = 13. ✓
Watch out. Check that both steps are done. Many answers stop after the first step.
Watch out
Watch out: many children stop after the first step. Read the whole question, and check whether it asks for one answer or two.
Exam tip
Grown-up tip. Ask your child to write "Step 1" and "Step 2" on a piece of paper, and to write the answer for each step. Ask: "Did you do the second step?"
Exercise 9F Two-step questions from charts and tables
Non-calculatorMethod. Add the number for dogs and the number for cats.
- Read the number for dogs. Read it from the table, chart or list.dogs = 10
- Read the number for cats. Read it from the table, chart or list.cats = 7
- Add the numbers together. Add every number to find the total.10 + 7 = 17
- Write the answer. The total is the answer.17
Check. 17 − 7 = 10, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for the dogs and cats. The number for the dogs and cats is 17 children.the dogs and cats = 17
- Find the number for hamsters. The number for hamsters is 4 children.hamsters = 4
- Subtract the smaller number from the bigger number. 17 is more than 4, so take 4 away from 17.17 − 4 = 13
- Write the answer. The difference is 13 children.13
Check. 4 + 13 = 17. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Method. Add the totals for Monday and Tuesday.
- Read the number for Monday. Read it from the table, chart or list.Monday = 11
- Read the number for Tuesday. Read it from the table, chart or list.Tuesday = 12
- Add the numbers together. Add every number to find the total.11 + 12 = 23
- Write the answer. The total is the answer.23
Check. 23 − 12 = 11, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Monday and Tuesday. The number for Monday and Tuesday is 23 children.Monday and Tuesday = 23
- Find the number for Wednesday. The number for Wednesday is 11 children.Wednesday = 11
- Subtract the smaller number from the bigger number. 23 is more than 11, so take 11 away from 23.23 − 11 = 12
- Write the answer. The difference is 12 children.12
Check. 11 + 12 = 23. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Method. Add the number for Pizza and the number for Pasta.
- Read the number for Pizza. Read it from the table, chart or list.Pizza = 9
- Read the number for Pasta. Read it from the table, chart or list.Pasta = 6
- Add the numbers together. Add every number to find the total.9 + 6 = 15
- Write the answer. The total is the answer.15
Check. 15 − 6 = 9, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Pizza and Pasta. The number for Pizza and Pasta is 15 children.Pizza and Pasta = 15
- Find the number for Wraps. The number for Wraps is 7 children.Wraps = 7
- Subtract the smaller number from the bigger number. 15 is more than 7, so take 7 away from 15.15 − 7 = 8
- Write the answer. The difference is 8 children.8
Check. 7 + 8 = 15. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the number of books for Monday and Tuesday.
- Read the number for Monday. Read it from the table, chart or list.Monday = 15
- Read the number for Tuesday. Read it from the table, chart or list.Tuesday = 20
- Add the numbers together. Add every number to find the total.15 + 20 = 35
- Write the answer. The total is the answer.35
Check. 35 − 20 = 15, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Monday and Tuesday. The number for Monday and Tuesday is 35 books.Monday and Tuesday = 35
- Find the number for Thursday. The number for Thursday is 30 books.Thursday = 30
- Subtract the smaller number from the bigger number. 35 is more than 30, so take 30 away from 35.35 − 30 = 5
- Write the answer. The difference is 5 books.5
Check. 30 + 5 = 35. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the number for Class 3A and the number for Class 3B.
- Read the number for Class 3A. Read it from the table, chart or list.Class 3A = 12
- Read the number for Class 3B. Read it from the table, chart or list.Class 3B = 8
- Add the numbers together. Add every number to find the total.12 + 8 = 20
- Write the answer. The total is the answer.20
Check. 20 − 8 = 12, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Class 3A and 3B. The number for Class 3A and 3B is 20 children.Class 3A and 3B = 20
- Find the number for Class 3C. The number for Class 3C is 15 children.Class 3C = 15
- Subtract the smaller number from the bigger number. 20 is more than 15, so take 15 away from 20.20 − 15 = 5
- Write the answer. The difference is 5 children.5
Check. 15 + 5 = 20. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the number of bottles for Class 3A and Class 3D.
- Read the number for Class 3A. Read it from the table, chart or list.Class 3A = 25
- Read the number for Class 3D. Read it from the table, chart or list.Class 3D = 30
- Add the numbers together. Add every number to find the total.25 + 30 = 55
- Write the answer. The total is the answer.55
Check. 55 − 30 = 25, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Class 3A and 3D. The number for Class 3A and 3D is 55 bottles.Class 3A and 3D = 55
- Find the number for Class 3B. The number for Class 3B is 40 bottles.Class 3B = 40
- Subtract the smaller number from the bigger number. 55 is more than 40, so take 40 away from 55.55 − 40 = 15
- Write the answer. The difference is 15 bottles.15
Check. 40 + 15 = 55. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the number of books for Cal and Eva.
- Read the number for Cal. Read it from the table, chart or list.Cal = 6
- Read the number for Eva. Read it from the table, chart or list.Eva = 4
- Add the numbers together. Add every number to find the total.6 + 4 = 10
- Write the answer. The total is the answer.10
Check. 10 − 4 = 6, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Bea. The number for Bea is 16 books.Bea = 16
- Find the number for Cal and Eva. The number for Cal and Eva is 10 books.Cal and Eva = 10
- Subtract the smaller number from the bigger number. 16 is more than 10, so take 10 away from 16.16 − 10 = 6
- Write the answer. The difference is 6 books.6
Check. 10 + 6 = 16. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the goals for the Falcons and the goals for the Owls.
- Read the number for the Falcons. Read it from the table, chart or list.the Falcons = 10
- Read the number for the Owls. Read it from the table, chart or list.the Owls = 6
- Add the numbers together. Add every number to find the total.10 + 6 = 16
- Write the answer. The total is the answer.16
Check. 16 − 6 = 10, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for the Falcons and the Owls. The number for the Falcons and the Owls is 16 goals.the Falcons and the Owls = 16
- Find the number for the Hawks. The number for the Hawks is 14 goals.the Hawks = 14
- Subtract the smaller number from the bigger number. 16 is more than 14, so take 14 away from 16.16 − 14 = 2
- Write the answer. The difference is 2 goals.2
Check. 14 + 2 = 16. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Add the points for Team A and Team B.
- Read the number for Team A. Read it from the table, chart or list.Team A = 35
- Read the number for Team B. Read it from the table, chart or list.Team B = 20
- Add the numbers together. Add every number to find the total.35 + 20 = 55
- Write the answer. The total is the answer.55
Check. 55 − 20 = 35, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Team A and Team B. The number for Team A and Team B is 55 points.Team A and Team B = 55
- Find the number for Team C. The number for Team C is 45 points.Team C = 45
- Subtract the smaller number from the bigger number. 55 is more than 45, so take 45 away from 55.55 − 45 = 10
- Write the answer. The difference is 10 points.10
Check. 45 + 10 = 55. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A two-step question needs two calculations. Use the answer from the first step in the second step.
Method. Find the total for Monday and Tuesday, then compare it with the total for Friday.
- Add the totals for Monday and Tuesday. Each day total is the boys and girls added together.11 + 12 = 23
- Read the total for Friday. Use the total for Friday from the table.Friday = 14
- Compare the two numbers. 23 is more than 14, so the statement is not right.23 > 14
- Decide. Mia is not right. Monday and Tuesday together had more children than Friday.No
Check. 14 is less than 23, so the answer is No. ✓
Watch out. Use the day totals from the table. Do not compare the boys with the girls.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Method. Add the numbers for every lunch to find the class total.
- Read the number for Pizza. Read it from the table, chart or list.Pizza = 9
- Read the number for Pasta. Read it from the table, chart or list.Pasta = 6
- Read the number for Jacket potato. Read it from the table, chart or list.Jacket potato = 4
- Read the number for Wraps. Read it from the table, chart or list.Wraps = 7
- Add the numbers together. Add every number to find the total.9 + 6 + 4 + 7 = 26
- Write the answer. The total is the answer.26
Check. 26 − 7 = 19, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many did not choose Pizza.
- Find the number for the whole class. The number for the whole class is 26 children.the whole class = 26
- Find the number for the children who chose Pizza. The number for the children who chose Pizza is 9 children.the children who chose Pizza = 9
- Subtract the smaller number from the bigger number. 26 is more than 9, so take 9 away from 26.26 − 9 = 17
- Write the answer. The difference is 17 children.17
Check. 9 + 17 = 26. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Chapter summary
| Skill | Method |
|---|---|
| Read a table | Find the row heading, then the column heading. The number where they meet is the answer. |
| Total in a table | Add the numbers in a row, or in a column, to find a total. |
| Read a pictogram | Count the whole pictures and multiply by the key. A half picture is half of the key. |
| Read a scaled bar chart | Count the squares up to the top of the bar, then multiply by the scale. |
| Count tally marks | Count the groups of five first, then add the single marks. |
| Draw a pictogram or bar chart | Divide the total by the key or the scale to find how many pictures or squares to draw. |
| How many more or fewer | Subtract the smaller number from the bigger number. |
| Two-step questions | Do the first step, then use its answer in the second step. Answer every part of the question. |
Can you…?
- I can read the numbers in a table, using the row and column headings.
- I can add the numbers in a row or a column to find a total.
- I can read a pictogram, using the key, including a half picture.
- I can read a scaled bar chart by counting the squares and multiplying by the scale.
- I can count tally marks in groups of five.
- I can work out how many pictures or squares a total needs.
- I can answer one-step questions: how many more and how many fewer.
- I can answer two-step questions, and check each step.
Key terms
- Table
- Information arranged in rows and columns.
- Row heading
- The word at the start of a row, on the left-hand side.
- Column heading
- The word at the top of a column.
- Data
- Information that we collect and count, such as the number of children who chose each pet.
- Pictogram
- A chart that uses pictures to show numbers.
- Key
- The part of a chart that tells you how much one picture or one square stands for.
- Scaled bar chart
- A bar chart in which one square stands for more than one unit.
- Tally
- A way of counting in groups of five marks.
- Difference
- The amount between two numbers, found by subtracting the smaller number from the bigger one.
- Two-step question
- A question that needs two calculations. The answer to the first step is used in the second.
Exercise 9Z Check-up
Non-calculatorRaffle tickets sold
| Class | Tickets |
|---|---|
| Class 3A | 18 |
| Class 3B | 23 |
| Class 3C | 9 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the column and the row, then read the number where they meet.
- Find the column heading. Look along the top row for Tickets.Column: Tickets
- Find the row heading. Look down the left-hand side for Class 3B.Row: Class 3B
- Read the number where they meet. Read across the row and down the column until they meet.Class 3B, Tickets = 23
- Write the answer. Write the number only.23
Check. 23 is the number in the Class 3B row under Tickets. ✓
Watch out. Read across the row, not down the column next to it.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Count the whole pictures, multiply by the key, then add any half picture.
- Find the row for Tuesday. Read along the row to see all of its pictures.Row: Tuesday
- Count the whole pictures and multiply by the key. Each whole picture stands for 5 stickers.5 × 5 = 25
- Write the answer. The whole pictures make the whole number.25
Check. 5 × 5 = 25. ✓
Watch out. Do not stop at the number of pictures. Multiply by the key first.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares up to the top of the bar, then multiply by the scale.
- Find the bar for Wednesday. Find the label under the bar.Bar: Wednesday
- Count the squares up to the top of the bar. Each square stands for 2 cups.8 squares
- Multiply the squares by the scale. Each square is worth 2, so multiply the squares by 2.8 × 2 = 16
- Write the answer. This is the number of cups.16
Check. 8 squares of 2 make 16. ✓
Watch out. Count the squares, then multiply. Do not write the number of squares as the answer.
Raffle tickets sold
| Class | Tickets |
|---|---|
| Class 3A | 18 |
| Class 3B | 23 |
| Class 3C | 9 |
Method. Read the number of tickets for each class, then add them together.
- Read the number for Class 3A. Read it from the table, chart or list.Class 3A = 18
- Read the number for Class 3B. Read it from the table, chart or list.Class 3B = 23
- Read the number for Class 3C. Read it from the table, chart or list.Class 3C = 9
- Add the numbers together. Add every number to find the total.18 + 23 + 9 = 50
- Write the answer. The total is the answer.50
Check. 50 − 9 = 41, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Tuesday. The number for Tuesday is 25 stickers.Tuesday = 25
- Find the number for Wednesday. The number for Wednesday is 5 stickers.Wednesday = 5
- Subtract the smaller number from the bigger number. 25 is more than 5, so take 5 away from 25.25 − 5 = 20
- Write the answer. The difference is 20 stickers.20
Check. 5 + 20 = 25. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many fewer.
- Find the number for Monday. The number for Monday is 12 cups.Monday = 12
- Find the number for Thursday. The number for Thursday is 6 cups.Thursday = 6
- Subtract the smaller number from the bigger number. 12 is more than 6, so take 6 away from 12.12 − 6 = 6
- Write the answer. The difference is 6 cups.6
Check. 6 + 6 = 12. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Method. Read the number for Monday and for Friday, then add them together.
- Read the number for Monday. Read it from the table, chart or list.Monday = 10
- Read the number for Friday. Read it from the table, chart or list.Friday = 20
- Add the numbers together. Add every number to find the total.10 + 20 = 30
- Write the answer. The total is the answer.30
Check. 30 − 20 = 10, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Divide the total by what one picture stands for.
- Write the total. We need to show 35 stickers.35 stickers
- Divide by how many one picture stands for. One picture stands for 5 stickers.35 ÷ 5 = 7
- Write the number of pictures. 7 whole pictures.7
Check. 7 × 5 = 35. ✓
Watch out. Divide, do not multiply. A bigger number of stickers needs more pictures.
Raffle tickets sold
| Class | Tickets |
|---|---|
| Class 3A | 18 |
| Class 3B | 23 |
| Class 3C | 9 |
Key words. A two-step question needs two calculations. Use the answer from the first step in the second step.
Method. Do the first step, then use its answer in the second step.
- Step 1: read the number for Class 3B. Read it from the chart or table.Class 3B = 23
- Step 1: read the number for Class 3C. Read it from the chart or table.Class 3C = 9
- Step 1: add the numbers together. This is the total for Class 3B and Class 3C.23 + 9 = 32
- Step 2: read the number for Class 3A. This is the number to compare with.Class 3A = 18
- Step 2: subtract the smaller number from the bigger number. The total of 32 is more than 18, so take 18 away from 32.32 − 18 = 14
- Write the answer. Both answers are needed: 32 tickets altogether, and 14 tickets more.14
Check. 18 + 14 = 32. ✓
Watch out. Check that both steps are done. Many answers stop after the first step.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Count the squares on the Tuesday bar, then multiply by the scale.
- Count the squares on the Tuesday bar. Count the squares up to the top of the bar.4 squares
- Multiply the squares by the scale. Each square stands for 2 cups.4 × 2 = 8
- Compare with what Ali said. Ali said 8 cups, which is the same.8 = 8
- Decide. So Ali is right.Yes
Check. 4 squares of 2 cups make 8 cups. ✓
Watch out. Count the squares, then multiply by the scale.
Total 22 marks. Allow about 22 minutes.
Exercise 9X Practice test questions
Non-calculatorKey words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Read every number, then find the fewest one.
- Read the number for Dogs. Read it from the chart.Dogs = 10
- Read the number for Cats. Read it from the chart.Cats = 7
- Read the number for Hamsters. Read it from the chart.Hamsters = 4
- Read the number for Fish. Read it from the chart.Fish = 3
- Find the smallest number. The fewest is the smallest number.smallest = 3
- Write the answer. Write the name with the number.Fish
Check. 3 is smaller than all the other numbers. ✓
Watch out. Read every bar or picture row before you choose. Check the key first.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide the total by what one square stands for.
- Write the total. We need to show 10 goals.10 goals
- Divide by how many one square stands for. One square stands for 2 goals.10 ÷ 2 = 5
- Write the number of squares. 5 whole squares.5
Check. 5 × 2 = 10. ✓
Watch out. Divide, do not multiply. A bigger number of goals needs more squares.
Children at the club, Monday to Friday
| Monday | Tuesday | Wednesday | Thursday | Friday | |
|---|---|---|---|---|---|
| Boys | 5 | 7 | 4 | 6 | 8 |
| Girls | 6 | 5 | 7 | 4 | 6 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the total for each day, then add the five totals together.
- Add the boys and the girls on Monday. Add the two numbers in that column.5 + 6 = 11
- Add the boys and the girls on Tuesday. Add the two numbers in that column.7 + 5 = 12
- Add the boys and the girls on Wednesday. Add the two numbers in that column.4 + 7 = 11
- Add the boys and the girls on Thursday. Add the two numbers in that column.6 + 4 = 10
- Add the boys and the girls on Friday. Add the two numbers in that column.8 + 6 = 14
- Add the five day totals. Add the totals for each day.11 + 12 + 11 + 10 + 14 = 58
- Write the answer. This is the number of children altogether.58
Check. The Friday total is 14, and the other days add to 44. ✓
Watch out. Add all five days. Do not add only the boys or only the girls.
Key words. A pictogram uses pictures to show numbers. The key tells you how many one picture stands for. A half picture is half of the key.
Method. Divide the total by what one picture stands for.
- Write the total. We need to show 45 books.45 books
- Divide by how many one picture stands for. One picture stands for 5 books.45 ÷ 5 = 9
- Write the number of pictures. 9 whole pictures.9
Check. 9 × 5 = 45. ✓
Watch out. Divide, do not multiply. A bigger number of books needs more pictures.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Take 15 away from the bottles for Class 3B, then find the class with that number.
- Read the number for Class 3B. Read it from the bar chart.Class 3B = 40
- Take 15 away. We want 15 fewer than Class 3B.40 − 15 = 25
- Find the class with that number. Look for the bar that reaches the same number.25 bottles = Class 3A
- Write the answer. Write the name of the class.Class 3A
Check. Class 3A has 25 bottles, and 25 + 15 = 40. ✓
Watch out. Check the bar for each class, not only the tallest bar.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Class 3B. The number for Class 3B is 8 children.Class 3B = 8
- Find the number for Class 3D. The number for Class 3D is 5 children.Class 3D = 5
- Subtract the smaller number from the bigger number. 8 is more than 5, so take 5 away from 8.8 − 5 = 3
- Write the answer. The difference is 3 children.3
Check. 5 + 3 = 8. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Favourite lunch in Class 3B
| Lunch | Children |
|---|---|
| Pizza | 9 |
| Pasta | 6 |
| Jacket potato | 4 |
| Wraps | 7 |
Key words. A table puts information in rows and columns. Read across a row and down a column to find the number where they meet.
Method. Find the total for the class and half of it, then compare the number for Pizza with half.
- Find the total for the class. Add all the lunches.9 + 6 + 4 + 7 = 26
- Find half of the class. Halve the total.26 ÷ 2 = 13
- Read the number for Pizza. Pizza is in the lunch table.Pizza = 9
- Compare. 9 is less than 13, so fewer than half chose Pizza.9 < 13
- Decide. So Ruby is not right.No
Check. 9 + 17 = 26. ✓
Watch out. Half is the total divided by 2. Compare the Pizza number with half of the class, not with the total.
Method. Add the number of books for Ali, Bea and Dev.
- Read the number for Ali. Read it from the table, chart or list.Ali = 12
- Read the number for Bea. Read it from the table, chart or list.Bea = 16
- Read the number for Dev. Read it from the table, chart or list.Dev = 10
- Add the numbers together. Add every number to find the total.12 + 16 + 10 = 38
- Write the answer. The total is the answer.38
Check. 38 − 10 = 28, which is the total of the other numbers. ✓
Watch out. Add every number, not only the first two.
Key words. How many more and how many fewer both ask for the difference between two numbers. Subtract the smaller number from the bigger number.
Method. Find both numbers, then subtract the smaller from the bigger to find how many more.
- Find the number for Ali, Bea and Dev. The number for Ali, Bea and Dev is 38 books.Ali, Bea and Dev = 38
- Find the number for Cal and Eva. The number for Cal and Eva is 10 books.Cal and Eva = 10
- Subtract the smaller number from the bigger number. 38 is more than 10, so take 10 away from 38.38 − 10 = 28
- Write the answer. The difference is 28 books.28
Check. 10 + 28 = 38. ✓
Watch out. Subtract the smaller number from the bigger one, not the other way round.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Add 5 points to the points that Team A already has.
- Read the points for Team A. Read it from the bar chart.Team A = 35
- Add the extra points. Team A scores 5 more points.35 + 5 = 40
- Write the answer. This is the new total for Team A.40
Check. 40 − 5 = 35. ✓
Watch out. Add the 5 points to the total, not to the number of squares.
Key words. In a scaled bar chart, one square stands for more than one unit. The key tells you how many one square stands for.
Method. Divide the total by what one square stands for.
- Write the total. We need to show 40 points.40 points
- Divide by how many one square stands for. One square stands for 5 points.40 ÷ 5 = 8
- Write the number of squares. 8 whole squares.8
Check. 8 × 5 = 40. ✓
Watch out. Divide, do not multiply. A bigger number of points needs more squares.
Key words. A tally counts in groups of five. Four upright marks and one line across them make a group of five.
Method. Count the votes for each colour, then add them together. Compare the total with what Tom said.
- Read the votes for each colour. Count the tally marks for each colour.Red 7, Blue 4, Yellow 6, Green 3
- Add the votes together. This is the total number of children who voted.7 + 4 + 6 + 3 = 20
- Compare with what Tom said. Tom said 22, but the total is 20.20 is not 22
- Decide. So Tom is not right.No
Check. 20 is the total of the four colours. ✓
Watch out. Add all four colours. Check the total against the tally marks.