Official Guide Explanation:
Data Sufficiency #47




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Solution and Metadata

Question: 47
Page: 277
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Rate Problems > other

Explanation: If two floors are 9 feet apart, then the stairway must have a total height of 9 feet. To find the number of steps that make up a 9 foot tall stairway, you need the height of each step.

Statement (1) provides that: if each step is (3/4) foot high, then the number of steps is (9/((3/4))) = 9((4/3)) = 12. Statement (2) is irrelevant: you need the height of the steps, not the width of them. Thus, the correct choice is (A).

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