Calculations involving percentages of quantities. Working with increases and decreases as well as expressing a quantity as a percentage of another quantity.
Part ofMathsNumeracy
This means working out the percentage. An example question of this would be:
\(15\) out of \(30\) pupils in a class are girls. Express this as a percentage.
\(\frac{{15}}{{30}} \times 100 = 50\%\)
Now try the example question below.
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 of protein:
\(= \frac{2}{{40}} \times 100 = 5\%\)
Percentage of fat:
\(= \frac{3}{{40}} \times 100 = 7.5\%\)
Percentage of carbohydrate:
\(= \frac{{35}}{{40}} \times 100 = 87.5\%\)
