GMAT Problem Solving (PS) | Re: By approximately what percent did the sale of nonfiction titles increa

In 1984, sale of nonfiction titles was 40,000, and in 1987, the sales were a bit less than 60,000. Thus:

(60,000 - 40,000)/40,000 x 100 = 20,000/40,000 x 100 = 50%

However, since the sales in 1987 were slightly less than 60,000, the percentage increase must be somewhat less than 50%, so the
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