Introducing Percentages

≈ 25 min

Percent means "per hundred". So $25\%$ is a short way of writing $\dfrac{25}{100}$ , which simplifies to $\dfrac{1}{4}$ . A few worth memorising:

50\% = \tfrac{1}{2}, \quad 25\% = \tfrac{1}{4}, \quad 10\% = \tfrac{1}{10}

Finding a percentage of an amount. $10\%$ of R $80$ means one tenth of R $80$ : $80 \div 10 = 8$ , so R $8$ . And $25\%$ of $60$ is one quarter: $60 \div 4 = 15$ .

Percentages are everywhere in the shops — a " $20\%$ off" sign at a spaza or clothing store, VAT on a till slip — so being quick with the easy ones pays off.

Written as a fraction in lowest terms, $50\%$ is…

$\dfrac{1}{4}$

$\dfrac{1}{2}$

$\dfrac{1}{5}$

$\dfrac{1}{3}$

Find $10\%$ of R $80$ . Give your answer in rand.

Find $25\%$ of $60$ .

A jacket costs R $200$ . In a sale it is marked " $20\%$ off". How many rand is the discount?