Official Guide Explanation:
Data Sufficiency #51




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Solution and Metadata

Question: 51
Page: 277
Difficulty: 5 (Moderate)
Category 1: Algebra > Inequalities > other
Category 2: Arithmetic > Fractions >
Category 3: Arithmetic > Properties of Integers > Other

Explanation: In order for ((x)/(y)) to be greater than 1, x must be greater than y. (That's only because the question stipulates that both are positive; if they could be negative, that would open up more possibilities.) So, the question is: "Is x greater than y?"

Statement (1) is insufficient: x could be greater than y, but as long as the product is greater than 1, y could also be greater than x. Statement (2) is sufficient: add y to both sides of x - y > 0 and x > y, which directly answers the question. (B) is the correct choice.

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