Official Guide Explanation:
Data Sufficiency #10

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Solution and Metadata

Question: 10
Page: 153
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Sets > 2 sets
Category 2: Word Problems > Sets >

Explanation: Statement (1) is not sufficient: it provides the occupancy rate of all single - family homes in City X, not those built last year. Statement (2) is also not sufficient: again, it addresses the total in City X, not the subset that was built last year.

Taken together, the statements are still insufficient: there is no information about the subset of homes built last year, or any indication that the percentage occupied among all homes in City X represents the percentage occupied among those built last year. (E) is the correct choice.

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