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Stage 8 · Fractions & decimals

Percentages, fractions and decimals

A percentage is a fraction out of 100.

How to do it

Method

A percentage is a fraction out of 100

14 = 25100 = 25%

Another way

Times 100%

14 × 100% = 25%

In full

A percentage is a fraction over 100. Decimal to percentage: move the point two places right, 0.35 = 35%; percentage to decimal: two places left, 45% = 0.45. Short of digits? Fill in zeros: 0.3 = 30%, 7% = 0.07. Fraction to percentage: scale it to a denominator of 100, 14 = 25100 = 25%; percentage to fraction: write it over 100 and simplify, 40% = 40100 = 25. Or multiply the decimal or fraction by 100%: 14 × 100% = 25% — the same answer.

Worked examples

Have a go first, then open each one for the answer and the working.

  1. Example 1

    88% = ?

    Answer as a decimal

    Show the answer and working

    Answer: 88% = 0.88

    88%: move the point two places left, 88 ÷ 100 = 0.88

  2. Example 2

    45% = ?

    Answer in simplest form

    Show the answer and working

    Answer: 45% = 920

    45% = 45100; simplify, dividing top and bottom by their highest common factor 5: 45 ÷ 5 = 9, 100 ÷ 5 = 20 → 920

  3. Example 3

    14 = ?%

    Show the answer and working

    Answer: 14 = 25%

    14: scale it to a denominator of 100, multiplying top and bottom by 25: 1 × 25 = 25, 4 × 25 = 100 → 25100 = 25%

  4. Example 4

    25% = ?

    Answer in simplest form

    Show the answer and working

    Answer: 25% = 14

    25% = 25100; simplify, dividing top and bottom by their highest common factor 25: 25 ÷ 25 = 1, 100 ÷ 25 = 4 → 14

Practise percentages, fractions and decimals in the game →Stage 8 · Fractions & decimals · Free to start, unlimited questions, no download