VT · Percentages

In each set, one thing changes and everything else stays the same. Work them out in order and look for the pattern — the last line tells you what to notice.

①Percentage of $200$: only the percentage changeschanging: the percentage
Work out each percentage of $200$.
$10\%$
=
$25\%$
=
$50\%$
=
$75\%$
=
Doubling the percentage doubles the answer. Spot the link between the $\%$ and the result.
②Increase $80$: only the percentage changeschanging: the percentage increase
Increase $80$ by each percentage (use a multiplier).
by $10\%$
=
by $25\%$
=
by $50\%$
=
A bigger percentage means a bigger multiplier, so a bigger result.
③The multiplier for a changechanging: the percentage change
Write the single multiplier for each percentage change.
increase by $20\%$
=
decrease by $20\%$
=
increase by $5\%$
=
decrease by $5\%$
=
Increase adds to $1$; decrease takes away from $1$. What do a matching increase and decrease multiplier add up to?

Answers · Percentages

Variation practice
① Percentage of $200$: only the percentage changes
$10\%$: 20$25\%$: 50$50\%$: 100$75\%$: 150
② Increase $80$: only the percentage changes
by $10\%$: 88by $25\%$: 100by $50\%$: 120
③ The multiplier for a change
increase by $20\%$: 1.2decrease by $20\%$: 0.8increase by $5\%$: 1.05decrease by $5\%$: 0.95
mathedup.co.uk · sheet 12ZO