Maths · KS3 and GCSE · Interactive lesson
Fractions, decimals and percentages
Show the same amount as a fraction, decimal and percentage. Change a hundred-square and practise finding percentages of amounts.
Choose your view
Explore an interactive example, then try the questions at your own pace.
KS3 / GCSE · start with the idea
By the end of this lesson: Show the same amount as a fraction, a decimal and a percentage.
The interactive diagram and controls are in Stage 2, “Explore one example”. Read the idea here, then try it next.
- A fraction, a decimal and a percentage can describe the same share.
- Imagine one whole split into 100 equal squares. Each square is 1% of that whole.
- Half of a whole is 1/2, or 0.5, or 50%.
Fifty of the hundred equal squares make half of the whole.
Useful starting points
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What do the words mean?
- Fraction
- A share of a whole, written with a top and bottom number.
- Decimal
- A number written using place value, such as 0.5.
- Percentage
- Parts out of 100. The symbol % means “per hundred”.
Change the example
This is the lesson example. Your practice question uses its own numbers.
Something to try
Keep the number of equal pieces the same. Shade one more piece. What changes in all three forms?
Notice what changes
How particle motion works +
Starts paused. Press Play, then add energy to see the warmer particles move faster.
Particles keep the same size. Liquid particles move around; solid particles vibrate around fixed positions. This is a simplified model, with the change in motion exaggerated to make it easier to see.
About the playback +
About this model
The grid is one whole: 100 squares. Each small square is 1%, or 0.01. Darker outlines show 2 equal pieces. The decimals in this tool end, so no rounding is needed.
More about this diagram
Still picture. Play particle motion in Stage 2.
1/2 = 0.5 = 50%
Still picture of the example from Stage 2. Use the back arrow to change it.
Work through it
Starting example: read the steps below
- The whole is split into 2 equal pieces. 1 piece is shaded.
- Fraction: 1/2.
- Decimal: 1 ÷ 2 = 0.5.
- Percentage: 0.5 × 100 = 50%. They all show the same share.
Try on your own
Your turn. No rush.
Question 1
Write 1/4 as a decimal.
About these questions
Questions appear in a mixed order. Work at your own pace and stop whenever you like.
These questions use their own numbers, separate from the lesson example. You can stop whenever you like. Answers last for this visit to the page.
A good place to pause
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Can you show the same share as a fraction, a decimal and a percentage?
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Notes for parents and tutors
These lessons cover selected KS3 and GCSE ideas for England; they are not a complete course. The level notes explain where GCSE methods or optional extensions begin. Maurice can help you choose material for your course and exam board.
The content draws on the DfE Maths curriculum, DfE Science curriculum and AQA GCSE Physics specification. Level labels are guidance, not exam-board endorsements. For AQA Radioactivity, calculating net decline as a ratio is Higher-tier work. Net means the overall change; ask Maurice whether this extension is relevant to your course. Explanations and practice were reviewed during development on 21 October 2026; Maurice should check their fit before assigning work.
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