Reception Maths Patterns: Doubles
Part of the Reception Maths patterns chapter. Chapter overview · whole chapter on one page
Doubles
Lily has 3 red cubes and 3 blue cubes. Her two groups are the same, so this is a double: 3 + 3 = 6.
Doubles are always even, because every thing in the total has a partner.
Key ideas
- A double is two equal groups added together.
- Doubles make even numbers.
- Check a double by making pairs.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 3. The two groups match.3 and 3
- Add them together. Count all the things.3 + 3 = 6
- Write the answer. 6
Check. Make pairs from 6: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 4. The two groups match.4 and 4
- Add them together. Count all the things.4 + 4 = 8
- Write the answer. 8
Check. Make pairs from 8: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 5. The two groups match.5 and 5
- Add them together. Count all the things.5 + 5 = 10
- Write the answer. 10
Check. Make pairs from 10: they all have a partner. ✓
Watch out. Doubles are always even.
Watch out
Watch out: 2 + 3 is not a double, because the two groups are different sizes.
Exam tip
Grown-up tip. Make two equal rows of buttons. Ask: “Are the rows the same? Does every button have a partner?”
Exercise 8D Doubles
Non-calculatorMethod. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 1. The two groups match.1 and 1
- Add them together. Count all the things.1 + 1 = 2
- Write the answer. 2
Check. Make pairs from 2: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 2. The two groups match.2 and 2
- Add them together. Count all the things.2 + 2 = 4
- Write the answer. 4
Check. Make pairs from 4: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 3. The two groups match.3 and 3
- Add them together. Count all the things.3 + 3 = 6
- Write the answer. 6
Check. Make pairs from 6: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 4. The two groups match.4 and 4
- Add them together. Count all the things.4 + 4 = 8
- Write the answer. 8
Check. Make pairs from 8: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 5. The two groups match.5 and 5
- Add them together. Count all the things.5 + 5 = 10
- Write the answer. 10
Check. Make pairs from 10: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 2. The two groups match.2 and 2
- Add them together. Count all the things.2 + 2 = 4
- Write the answer. 4
Check. Make pairs from 4: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 4. The two groups match.4 and 4
- Add them together. Count all the things.4 + 4 = 8
- Write the answer. 8
Check. Make pairs from 8: they all have a partner. ✓
Watch out. Doubles are always even.
Key words. An even number can be made into pairs. An odd number has one left over.
Method. Put the things in pairs. If every thing has a partner, the number is even. If one is left over, it is odd.
- Make pairs from the 6 things. Put two things together in each pair.3 pairs
- Look for a left-over thing. A left-over thing means there is no partner.0 left over
- Write the answer. even
Check. Count the pairs: 3 pairs, and 0 left over. ✓
Watch out. An even number can be made into pairs with none left over.
Method. A double is two equal groups. Add the same number twice. The total is even.
- Make two equal groups of 4. The two groups match.4 and 4
- Add them together. Count all the things.4 + 4 = 8
- Write the answer. 8
Check. Make pairs from 8: they all have a partner. ✓
Watch out. Doubles are always even.
Method. A double has two equal groups.
- Look at 2 and 3. Two and three are different.2 and 3
- Check the groups. The groups are not the same size.2 is not 3
- Write the answer. No. The two groups are not the same size.
Check. Make two groups: 2 and 3. They do not match. ✓
Watch out. Both parts must be the same size.
Method. Find two equal groups that make 8.
- Make two equal groups. Each group has the same number.4 and 4
- Add them together. Four and four make eight.4 + 4 = 8
- Write the answer. 4 + 4 = 8
Check. Make pairs from 8: four pairs. ✓
Watch out. Both groups must be the same size.
Method. Think about pairs.
- Look at a double. Two equal groups.two equal groups
- Make pairs. Each thing in one group has a partner in the other group.pairs
- Write the answer. Accept any answer: each thing in a double has a partner in the other group.
Check. Make pairs from 6: 3 + 3 makes three pairs. ✓
Watch out. Every double makes pairs with nothing left over.