Official Guide Explanation:
Data Sufficiency #D47




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Solution and Metadata

Question: D47
Page: 25
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Sets > 2 sets
Category 2: Word Problems > Sets >

Explanation: This is an overlapping sets question. We're given the total, and we're given the amounts represented by the two sets, but we don't know how many books are in both sets, or how many are in neither set. We can use the following formula:

80 = 24 + 23 - both + neither

Statement (1) is sufficient. There are 24 fiction books. If 6 more of those were not written in Spanish than written in Spanish, 15 were not written in Spanish and 9 were written in Spanish. That answers the question.

Statement (2) is also sufficient. Of the 23 Spanish books, if 5 more are nonfiction than fiction, 14 are nonfiction and 9 are fiction. Choice (D) is correct.

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