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Home > Maths I > Numbers and Money > Percentages

Maths I


Expressing one quantity as a percentage of another

This means working out the percentage.


15 out of 30 pupils in a class are girls. Express this as a percentage.


{15 \over 30} \times 100 \% = 50 \%


Try the question below. Make sure you do the examples on paper before you check the answers.



A new healthy snack bar called "Fibre-crunch" is being sold in the shops. Each bar weighs 40g and contains 2g of protein, 3g of fat and 35g of carbohydrate. What percentage of protein, fat and carbohydrate does "Fibre-crunch" contain?

  • Percentage protein

    = {2 \over 40} \times 100 \%


  • = 5%


  • Percentage fat

    = {3 \over 40} \times 100 \%


  • = 7.5%


  • Percentage carbohydrate

    = {35 \over 40} \times 100 \%


  • = 87.5%


Crowd at a football stadium.

Class Clips

Video clip about how percentages are used to manage football fans in a stadium


A woman shopping a supermarket.

Class Clips

Video clip about how percentage change in prices through inflation affects consumers


A picture of Mia Cadaver

Tombstone Timeout

Swot up your sums with Mia Cadaver's maths game

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