percentage of an amount (2)...percentage of an amount (2) 1 a) use the bar model to find10% of 500...
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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.