The number of books in her summer reading list is = 20
The number of books that has been read by Emma = 14
The percentage of books that has been read by Emma = 70%
But the percentage of books in Emma summer reading list = 100%
∴ The number of books in her reading list= ˣ
That is ;
70% = 14
100% = ˣ
Make ˣ the subject of formula,
ˣ = 100 × 14 / 70
ˣ = 20
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