Percentages as operators Worked Solutions — GCSE Maths

Understand what $10\%$ means

$10\%$ means $10$ out of every $100$, which is exactly one tenth. To find one tenth of something you just divide by $10$.

Divide the amount by $10$

Dividing £80 by $10$ makes every digit one place smaller. That gives £8.

State the answer

So $10\%$ of £80 is £8. This is an exact value, no rounding needed.

Understand what $50\%$ means

$50\%$ is exactly one half. To find a half of something you divide by $2$.

Halve the amount

Half of $46$ is $23$.

State the answer

So $50\%$ of $46$ is $23$ - an exact value.

Understand what $25\%$ means

$25\%$ is exactly one quarter. To find a quarter you divide by $4$ (or halve, then halve again).

Divide the amount by $4$

A quarter of £60 is £15.

State the answer

So $25\%$ of £60 is £15.

Understand what $10\%$ means

$10\%$ means $10$ out of every $100$, which is exactly one tenth. To find one tenth of something you just divide by $10$.

Divide the amount by $10$

Dividing $350$ g by $10$ makes every digit one place smaller. That gives $35$ g.

State the answer

So $10\%$ of $350$ g is $35$ g. This is an exact value, no rounding needed.

Understand what $1\%$ means

$1\%$ means $1$ out of $100$, which is one hundredth. To find $1\%$ you divide by $100$.

Divide the amount by $100$

Dividing £400 by $100$ gives £4.

State the answer

So $1\%$ of £400 is £4.