A unit fraction
A unit fraction has 1 on top, like 12, 13 or 16.
Find 16 of 30
- Divide by the bottom number: 30 ÷ 6 = 5.
- The top number is 1, so you only need one part. 16 of 30 = 5.
Maths › Fractions and percentages › Fractions
A friendly guide for children and the grown-ups helping them. What a fraction is, finding fractions of amounts, equivalent fractions, mixed numbers, and adding, subtracting, multiplying and dividing. There’s a fraction machine to check answers and free printable worksheets from halves and quarters up to Key Stage 3.
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A fraction is part of a whole that has been cut into equal parts. The most important word is equal. If you cut a sandwich into 4 pieces and they are all different sizes, you haven’t made quarters.
Every fraction has two numbers, one on top of the other:
A handy way to remember: denominator and down both start with d. So 35 means “the whole is cut into 5 equal parts, and we have 3 of them”.
A fraction wall shows one whole at the top, then the same length cut into halves, thirds, quarters and so on. The more parts you cut it into, the smaller each part gets.
Fractions have their own place on the number line. Here the gap between each whole number is cut into quarters. 12 sits halfway between 0 and 1, and fractions keep going past 1.
To find a fraction of a number, remember: divide by the bottom, times by the top. Dividing by the bottom number tells you what one part is worth. Multiplying by the top number counts up the parts you need.
A unit fraction has 1 on top, like 12, 13 or 16.
Find 16 of 30
Use a bar to see it.
Find 35 of 40
Check it makes sense. 35 is a bit more than a half. Half of 40 is 20, so the answer should be a bit more than 20. 24 looks right.
Equivalent fractions are worth the same amount, even though they look different. On the fraction wall, 12 lines up exactly with 24, 36, 48, 510 and 612. They all cover the same length.
To make an equivalent fraction, multiply the top and the bottom by the same number. You cut every part into the same number of smaller pieces, so the amount doesn’t change.
23: multiply the top and the bottom by 4.
2 × 4 = 8 and 3 × 4 = 12, so 23 = 812.
34 = ?20. What turns 4 into 20? It’s × 5.
Do the same to the top: 3 × 5 = 15, so 34 = 1520.
Only multiply or divide. Adding the same number to the top and bottom does not work: 12 is not the same as 23.
Simplifying means writing a fraction with the smallest numbers you can, without changing its value. Divide the top and the bottom by the same number. When no number bigger than 1 goes into both, the fraction is in its simplest form.
Simplify 1824
Find the highest common factor: the biggest number that divides into both.
Factors of 18: 1, 2, 3, 6, 9, 18. Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24. The biggest one in both lists is 6.
18 ÷ 6 = 3 and 24 ÷ 6 = 4, so 1824 = 34.
The parts are the same size, so compare the top numbers.
59 is bigger than 29, because 5 parts is more than 2 parts of the same size.
The bigger the bottom number, the smaller each part.
13 is bigger than 15. Sharing a cake between 3 people gives bigger slices than sharing it between 5.
Make the bottom numbers the same first.
Which is bigger, 23 or 35? Both 3 and 5 go into 15. 23 = 1015 and 35 = 915, so 23 is bigger.
To order fractions, do the same thing with all of them. To put 34, 58 and 12 in order, write them all in eighths: 68, 58 and 48. Smallest first, that’s 12, 58, 34.
When the top number is bigger than the bottom number, the fraction is more than 1 whole. 114 is called an improper fraction. You can also write it as a mixed number: a whole number and a fraction, 234.
114: how many whole 4s are in 11?
11 ÷ 4 = 2 remainder 3. That’s 2 wholes and 3 quarters left over: 234.
325: each whole is 55, so 3 wholes are 15 fifths.
3 × 5 + 2 = 17, so 325 = 175.
Add or subtract the top numbers. The bottom number stays the same, because the size of the parts doesn’t change.
27 + 37 = 57
2 sevenths and 3 more sevenths make 5 sevenths.
79 − 49 = 39
7 ninths take away 4 ninths leaves 3 ninths. You can simplify the answer: 39 = 13.
If an answer goes past 1, such as 45 + 35 = 75, you can write it as 125.
Change the fractions so they have the same bottom number first, using equivalent fractions. Then add or subtract the tops.
12 + 38
13 + 14
212 − 134
Type in your own fractions to check an answer and see the working, with a picture.
Use whole numbers in the fraction boxes. The top goes in the top box and the bottom in the bottom box.
Children start this in Year 5 and Year 6. Here are the main kinds, with the simplest first.
Multiply the top number. The bottom stays the same.
35 × 4 = 125 = 225. It’s the same as adding 35 four times.
Multiply the tops, then multiply the bottoms.
14 × 12 = 18. Half of a quarter is an eighth.
23 × 34 = 612, which simplifies to 12.
Multiply the bottom number by the whole number.
13 ÷ 2 = 16. Cut a third into 2 equal pieces and each piece is a sixth.
When the top divides exactly, you can divide the top instead: 45 ÷ 2 = 25.
Ask “how many of these fit into that?”
34 ÷ 18: there are 6 eighths in 34, so the answer is 6.
The quick way: turn the second fraction upside down and multiply. 34 × 81 = 244 = 6.
Multiplying can make things smaller. Multiplying by a fraction less than 1 means taking part of something, so the answer is smaller than you started with. 12 × 10 = 5.
A fraction is a division. 38 means 3 ÷ 8, which is 0.375. That’s how you turn any fraction into a decimal.
Going the other way, read the decimal’s place value: 0.43 is 43 hundredths, so 0.43 = 43100. 0.6 is 6 tenths, so 0.6 = 610 = 35. A percentage is a fraction out of 100: 43% = 43100.
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There’s much more on percentages in our Percentages made easy guide.
Sometimes you know the part and need the whole. Find one part, then multiply by the bottom number.
A quarter of a number is 9. What is the number?
There are 4 quarters in a whole, so the whole is 9 × 4 = 36.
25 of a ribbon is 14 cm. How long is the whole ribbon?
2 parts are 14 cm, so 1 part is 14 ÷ 2 = 7 cm. There are 5 parts, so the ribbon is 7 × 5 = 35 cm.
For parents. Real things to share and fold come first: the numbers make much more sense after that.
In England, the National Curriculum builds fractions up step by step. The examples below are our own.
Paraphrased from the National Curriculum for England. Schools only have to cover each key stage’s content by the end of that key stage, so the year your child meets each idea can vary.
The key ideas on one A4 sheet: a fraction wall, the main methods and the fractions, decimals and percentages everyone should know. Stick it on the fridge or in their maths book.
Choose a sheet to see it below, then print it.
Pick an age, then a kind of sheet. Every roll makes a fresh sheet with an answer page.
A week of fractions for one child in one download: practice sheets that build step by step, with the cheat sheet from age 7. Answers are at the back.
4 sheets + 4 answer pages · 8 pages
Download the pack PDF, 336 KB6 sheets + 5 answer pages · 11 pages
Download the pack PDF, 537 KB7 sheets + 6 answer pages · 13 pages
Download the pack PDF, 603 KB5 sheets + 4 answer pages · 9 pages
Download the pack PDF, 448 KBEach pack is a PDF to print at home on A4, with the answers at the back. Every sheet in them can also be made fresh above. Each cover shows a real sheet from that pack.