1fully worked

Increase $40$ by $20\%$.

1multiplier $=1+0.20=1.2$Multiplier $=1+\dfrac{p}{100}$

2$40\times1.2=48$Multiply the amount by it

Check - Why is the multiplier $1.2$ and not $0.2$?

A you keep the original $100\%$ AND add $20\%$, so $120\%=1.2$B because $20\%=1.2$C a mistake – it should be $0.2$D because $40$ is even

2fully worked

Increase $60$ by $15\%$.

1multiplier $=1+0.15=1.15$Multiplier $=1+\dfrac{p}{100}$

2$60\times1.15=69$Multiply the amount by it

Check - What multiplier would DECREASE by $15\%$ instead?

A $1.15$B $0.85$C $0.15$D $1.5$

3you finish it

Increase $200$ by $8\%$.

1multiplier $=1.08$Multiplier $=1+\dfrac{p}{100}$

2Multiply the amount by it

Check - What is $8\%$ written as part of the multiplier?

A $0.8$B $0.08$C $8.0$D $1.8$

4you do it all

Increase $45$ by $40\%$.

1Multiplier $=1+\dfrac{p}{100}$

2Multiply the amount by it

Check - To go back from $63$ to $45$ you would...

A divide $63$ by $1.4$B divide $63$ by $0.4$C multiply by $1.4$D subtract $40$