Websink Prep UKKS2 MathsYear 4 chaptersMaths textbooksYear 1Year 2Year 4Year 5Year 6GCSEBrowse allPast papersFind a tutorBecome a tutor
Primary Maths · Year 4Chapter 5 · Fractions
Year 4 · Fractions · Lesson 5.5

Year 4: Comparing and ordering fractions

Part of the Year 4 fractions chapter. Chapter overview · whole chapter on one page · Download worksheet (PDF) · Answers (PDF)

Download worksheet (PDF)Answers (PDF)
5.5

Comparing and ordering fractions

Year 4
Compare and order fractions with the same denominator, Use a fraction wall, Unit fractions with different denominators

To compare two fractions means to say which one is bigger. We use the signs < (less than) and > (greater than), and = (equal to).

Same bottom number. The pieces are the same size, so the fraction with more pieces is bigger. Compare the top numbers. 5/8 is bigger than 3/8, because 5 pieces are more than 3 pieces.

3858
3/8 < 5/8. With the same bottom number, the bigger top number is the bigger fraction.

Unit fractions with different bottom numbers. Cut a whole into 4 equal parts, and another whole into 8 equal parts. The more parts you cut, the smaller each part is. So 1/8 is smaller than 1/4. A fraction wall shows this well.

11/21/21/31/31/31/41/41/41/41/61/61/61/61/61/61/81/81/81/81/81/81/81/8
On the wall, 1/8 is a shorter brick than 1/4. So 1/8 < 1/4.

Different bottom numbers, harder fractions. Make the bottom numbers the same using equivalent fractions (Section 5.3). To compare 3/4 and 5/8, change 3/4 into eighths: 3/4 = 6/8. Now compare 6/8 and 5/8. 6 is more than 5, so 3/4 is more than 5/8.

346858
3/4 = 6/8, and 6/8 is longer than 5/8.

Ordering means putting fractions in a list from smallest to biggest (or biggest to smallest). Give them all the same bottom number, then order the top numbers. A handy trick is to compare with one half. Half of 12 is 6, so 7/12 is more than a half and 5/12 is less than a half.

Key words. To compare is to say which is bigger. To order is to put things in a list from smallest to biggest, or the other way round.

Key ideas

  • Same bottom number: the bigger top number is the bigger fraction.
  • Unit fractions: the bigger the bottom number, the SMALLER the fraction. (1/8 < 1/4)
  • Different bottom numbers: change one fraction into an equivalent fraction so the bottom numbers match.
  • A fraction wall shows the sizes: a longer brick is a bigger fraction.
  • Compare with 1/2: half of the bottom number is the top number of a half.
  • < means less than. > means greater than.
Worked example 5.5.1
Write < or > in the box.   38  [ ]   58

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. When the bottom numbers are the same, the pieces are the same size. The fraction with the bigger top number is bigger.

  1. Look at the bottom numbers. They are both 8, so the pieces are the same size.
    38 and 58
    3858
  2. Compare the top numbers. The same size pieces: more pieces means a bigger fraction.
    3 < 5
  3. Write the answer.
    38 < 58

Check. Think of bars or a fraction wall: the longer shaded bar is the bigger fraction. ✓

Watch out. Only compare the top numbers when the bottom numbers are the same.

Worked example 5.5.2
Which is bigger, 1/5 or 1/8?

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. For unit fractions (1 on the top), the bigger the bottom number, the smaller the piece. Use a fraction wall to see it.

  1. Look at the bottom numbers. They are different: 5 and 8. The pieces are not the same size.
    15 and 18
    11/51/51/51/51/51/81/81/81/81/81/81/81/8
  2. Think about the size of the pieces. When you cut a whole into MORE equal parts, each part is SMALLER.
    5 parts: each part is bigger. 8 parts: each part is smaller.
  3. Write the answer. The fraction with the bigger bottom number is the smaller fraction (for unit fractions).
    15 > 18

Check. Think of bars or a fraction wall: the longer shaded bar is the bigger fraction. ✓

Watch out. 1/8 is smaller than 1/4. A bigger bottom number does not mean a bigger fraction!

Worked example 5.5.3
Write these fractions in order, smallest first.   79,  29,  49,  19

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. The bottom numbers are the same, so put the fractions in order using their top numbers, smallest first.

  1. Look at the bottom numbers. They are all 9, so the pieces are the same size and we can order the fractions by their top numbers.
    79,  29,  49,  19
  2. Put the top numbers in order. The bottom numbers are the same, so the bigger top number is the bigger fraction. We want smallest first.
    1, 2, 4, 7
  3. Write the ORIGINAL fractions in that order. The question uses the original fractions.
    19,  29,  49,  79

Check. Look at the picture: the bars get longer from left to right in the list. ✓

19294979

Watch out. Write the original fractions in your answer, not the rewritten ones.

Worked example 5.5.4
Write < or > in the box.   34  [ ]   58

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. Change one fraction so both have the same bottom number. Then compare the top numbers.

  1. Look at the bottom numbers. They are different. But 8 is in the 4 times table, so we can change 34 into eighths.
    4 × 2 = 8
  2. Rewrite 34 as eighths. Multiply the top and the bottom by the same number.
    34 = 68
    346858
  3. Compare the top numbers. Now the bottom numbers are the same (8).
    6 and 5: 6 > 5
  4. Write the answer.
    34 > 58

Check. Think of bars or a fraction wall: the longer shaded bar is the bigger fraction. ✓

Watch out. Do not compare the bottom numbers or the top numbers on their own. Make the bottom numbers the same first.

Worked example 5.5.5
Write these fractions in order, smallest first.   12,  16,  13,  110

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. For unit fractions, the bigger the bottom number, the smaller the piece. Use a fraction wall to see it.

  1. Look at the bottom numbers. These are all unit fractions (1 on the top). The bottom number tells us how many equal parts the whole is cut into.
    2, 6, 3, 10
  2. Think about the size of the pieces. More parts means smaller pieces. So the bigger the bottom number, the smaller the fraction.
    Biggest bottom number 10: smallest piece.
    Smallest bottom number 2: biggest piece.
    11/21/21/31/31/31/61/61/61/61/61/61/101/101/101/101/101/101/101/101/101/10
  3. Put them smallest first.
    110,  16,  13,  12

Check. On the wall the shaded bricks get shorter as we read down. ✓

Watch out. 5 is bigger than 3, but 1/5 is smaller than 1/3.

Worked example 5.5.6
Is 5/12 more than, less than or equal to 1/2?

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. Half of the bottom number is the top number of a half. Compare the top number with it.

  1. Find half of the bottom number. The whole is 12 parts. Half of the whole is half of 12 parts.
    12 ÷ 2 = 6, so 612 = 12
  2. Compare the top number 5 with 6. If we have more than 6 parts we have more than a half.
    5 < 6
  3. Write the answer.
    512 is less than 12

Check. 12 = 612, and 512 is less than 612. ✓

Watch out. Compare the top number with HALF of the bottom number, not with the bottom number itself.

Worked example 5.5.7
Write these fractions in order, smallest first.   12,  38,  34

Key words. To compare is to say which is bigger. < means “is less than” and > means “is greater than”.

Method. Give the fractions the same bottom number. Then put the top numbers in order, smallest first.

  1. Find a bottom number that all the bottom numbers go into. The biggest bottom number is 8. The other bottom numbers (2, 4) all go into 8.
    Use eighths.
  2. Rewrite every fraction as eighths. Multiply the top and the bottom by the same number each time.
    12 = 48  (× 4)
    38 = 38
    34 = 68  (× 2)
  3. Put the top numbers in order. The bottom numbers are the same, so the bigger top number is the bigger fraction. We want smallest first.
    3, 4, 6
  4. Write the ORIGINAL fractions in that order. The question uses the original fractions.
    38,  12,  34

Check. Look at the picture: the bars get longer from left to right in the list. ✓

381234

Watch out. Write the original fractions in your answer, not the rewritten ones.

Watch out

A bigger bottom number does not mean a bigger fraction. 1/8 is smaller than 1/4, even though 8 is bigger than 4. The bottom number says how many parts the whole is cut into. More parts means smaller parts. Also, only compare the top numbers when the bottom numbers are the same.

Exercise 5E  Comparing and ordering fractions

Non-calculator
1
FWhich fraction is bigger? The bars will help you.
(a)
3858
38 or 58
(b)
710410
710 or 410
(c)
2515
25 or 15
2
FQuick-fire! Write <, > or = in each box.
(a)25  [ ]   45
(b)78  [ ]   38
(c)59  [ ]   59
(d)16  [ ]   56
(e)910  [ ]   710
(f)412  [ ]   1112
3
FQuick-fire! These are unit fractions. Write < or > in each box.
(a)14  [ ]   16
(b)13  [ ]   12
(c)110  [ ]   15
(d)18  [ ]   112
(e)12  [ ]   19
(f)17  [ ]   14
4
FWrite each set of fractions in order, smallest first.
(a)37,  67,  17,  57
(b)56,  26,  46
(c)810,  310,  910,  110
5
FThese are all unit fractions. Write them in order, biggest first.
(a)13,  18,  15
(b)110,  12,  14,  15
(c)112,  16,  13
6
FUse the fraction wall or equivalent fractions. Write < or > in each box.
11/21/21/31/31/31/41/41/41/41/51/51/51/51/51/61/61/61/61/61/61/81/81/81/81/81/81/81/81/101/101/101/101/101/101/101/101/101/10
(a)12  [ ]   38
(b)34  [ ]   58
(c)23  [ ]   56
(d)14  [ ]   38
(e)25  [ ]   710
7
FIs each fraction more than, less than or equal to a half?
(a)38 is ... 12
(b)712 is ... 12
(c)510 is ... 12
(d)46 is ... 12
(e)310 is ... 12
(f)612 is ... 12
8
FWrite each set of fractions in order. Change the fractions so they have the same bottom number first.
(a)Smallest first: 12,  58,  34
(b)Biggest first: 56,  23,  12,  16
9
PSAmira drinks 3/5 of a bottle of water. Jack drinks 7/10 of an identical bottle. Who drinks more water? Show how you know.
35710
10
PSPriya eats 3/8 of a bar of chocolate. Sam eats 1/2 of an identical bar. Leo eats 5/8 of another identical bar. Write the fractions in order, biggest first.
11
RTom says, “18 is bigger than 14, because 8 is bigger than 4.” Is Tom right? Explain.
12
RWhich fraction is the odd one out?   58   46   310   712. Explain.
13
RAlways, sometimes or never?   The fraction with the bigger bottom number is the smaller fraction.
14
RHow many fractions with a bottom number of 8 are bigger than 14 and smaller than 58? Write them down.

Websink Prep UK is an independent site. It is not affiliated with, endorsed by or sponsored by AQA, Pearson Edexcel, OCR, WJEC, Eduqas, CCEA, SQA, GL Assessment, CEM or the Department for Education. All exam board names and trademarks belong to their owners. Past papers are linked from the exam boards' own websites and are not hosted here.

About Websink Prep UK · Find a tutor · Privacy · Terms · Cookie settings