percentage of an amount (2) - schudio · use dora’s method to complete the calculations. a) 5% of...

Percentage of an amount (2)

1 a) Usethebarmodeltofind10%of500

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

?

500

10%of500=

b) Useyouranswertoparta)tohelpyoucompletethecalculations.

20%of500= 70%of500=

90%of500= 60%of500=

30%of500= 100%of500=

2

UseDora’smethodtocompletethecalculations.

a) 5%of40= d)5%of2,000=

b) 5%of400= e)5%of6,000=

c) 5%of4,000=

Whatdoyounoticeaboutyouranswers?

3 Somechildrenareaskedtofind75%of340

a) UseDexter’smethodtofind75%of340

b) UseAlex’smethodtofind75%of340

©WhiteRoseMaths2019

To find 5% you can find 10% and then halve it.

I will find 25% and multiply it by 3

I will find 10% and multiply it by 7, then find 5% and add them together.

c) UseAmir’smethodtofind75%of340

d) Arethereanyothermethodsyoucoulduse?

4 Talktoapartneraboutdifferentmethodsforfindingthese

percentages.

20%90%60%15%55%40%

Useyourpreferredmethodtocalculatethepercentages.

a) 20%of1,000= d) 15%of1,000=

20%of550= 15%of300=

20%of40= 15%of30=

b) 90%of1,000= e) 55%of1,000=

90%of4,230= 55%of4,400=

90%of90= 55%of8=

c) 60%of1,000= f) 40%of1,000=

60%of400= 40%of400=

60%of98= 40%of98=©WhiteRoseMaths2019

5 Roniscalculatingthesepercentages.

10%of2020%of10

HowdoesRonknowthis?

6 a) Completethecalculations.

20%of40= 25%of60=

40%of20= 60%of25=

b) Whatdoyounoticeabouttheanswers?

c) Doesthisalwayshappen?Investigatewithotherexamples.

d) Talkaboutyourfindingswithapartner.

20% is double 10%, and 10 is half of 20, so I know

these will both have the same answer.

I will find 25% and 50% and add them together.