Part A:
Percentage of children that chose grapes = 30%
Percentage of children that chose apples = 25%
Difference = 30 - 25 = 5%
20 more children chose grapes than apples
⇒ 5% = 20 children
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Find 1% :
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5% = 20 children
1% = 20 ÷ 5
1% = 4 children
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Find 100% :
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1% = 4 children
100% = 4 x 100
100% = 400 children
Part B:
25% = 90°
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Find 1% :
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25% = 90°
1% = 90 ÷ 25
1% = 3.6°
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Find 31% (Mango) :
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1% = 3.6°
31% = 3.6 x 31
31% = 111.6°
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Answer:
(a) 400 children
(b) 111.6°
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