Question 820001
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1. 4/20 = x/35
20x = 140
x = 7 i.e. 7days
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2. 8/72 = a/99
72a = 792
a = 11 i.e. 11days
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3. 11/22 = 12/y
11y = 264
y = 24 i.e. 24cm
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4. 5/10 = 9/z
5z = 90
z = 18 i.e. 18books