10% of £170
£17
10% of £630
£63
10% of £1010
£101
20% of £455
£91
10% of £1130
£113
10% of £250
£25
25% of £140
£35
25% of £364
£91
25% of £68
£17
5% of £1340
£67
20% of £175
£35
50% of £202
£101
5% of £2260
£113
50% of £98
£49
10% of £490
£49
5% of £220
£11
20% of £125
£25
25% of £268
£67
5% of £1560
£78
5% of £1260
£63
50% of £22
£11
Answers are in pairs. Which is the odd one out?
Topics: Starter  Percentages
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%  This is the percent symbol.
Percent means 'out of 100'.
As 50 is half of 100, then 50% means half. To find 50% of a quantity you need to halve (or divide by two). So 50% of 6 is 3.
As 10 is one tenth of 100, then 10% means 'one tenth of'. To find 10% of a quantity you need to divide it by ten. So 10% of 800 is 80.
As 25 is one quarter of 100, then 25% means 'one quarter of'. To find 25% of a quantity you need to divide it by four. So 25% of 20 is 5.
Another way of finding 25% of a quantity is first finding 50% then dividing the result by 2.
As 33⅓ is one third of 100, then 33⅓% means 'one third of'. To find 33⅓% of a quantity you need to divide it by three. So 33⅓% of 30 is 10.
As 1 is one hundredth of 100, then 1% means 'one hundredth of'. To find 1% of a quantity you need to divide it by 100. So 1% of 800 is 8.
Other percentages can be found by combining some of the techniques mentioned above. Here are some examples:
If you need to use a calculator to check your working. See Calculator Workout skill 3.
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