Fractions, decimals and percentages
Choose your practice ↓Fractions, decimals and percentages are three ways of writing the same thing, and the primary curriculum spends six years making the connections between them secure: equivalent fractions, comparing and ordering, adding and subtracting with different denominators, multiplying and dividing fractions, and converting between the three forms. Percentages of amounts arrive last. This is the primary topic that most often decides how a student later copes with GCSE ratio and proportion. Phase 2 will cover Years 1 to 6 in full.
📚 What you learn here
- Equivalent fractions, simplifying, and comparing and ordering fractions
- Adding and subtracting fractions with the same and with different denominators
- Multiplying and dividing fractions, including by whole numbers
- Tenths, hundredths and decimal notation
- Converting between fractions, decimals and percentages, and finding a percentage of an amount
Frequently asked questions
Why can't I just add the numerators and the denominators?
Because fifths and quarters are different-sized pieces. The fractions must be rewritten over a common denominator before the numerators are added — this is still one of the commonest errors at GCSE.
Which conversions should be known by heart?
A half, a quarter, three quarters, a fifth, a tenth and their decimal and percentage forms. They save time in every later topic.
✍️ Written by the MathsUK teamChecked against the National Curriculum and GCSE specifications