Question

Kim has read 42 pages of a book. That is 20% of the total number of pages. How many pages long is Kim's book?

Answer 1

20% is 1/5 of 100, so we multiply 42 by 5 to get 210.
Therefore, Kim's book is 210 pages long.
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Hope this helps!
==jding713==

Answer 2

Hi there! The answer is 210 pages.

We can find our answer by looking at the proportions:
20 % is 42 pages.
10 % is 21 pages (42 / 2).
100% is 210 pages. (21 × 10).