Official Guide Explanation:
Data Sufficiency #120




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Solution and Metadata

Question: 120
Page: 161
Difficulty: 6 (Moderately Difficult)
Category 1: Algebra > Absolute Value >
Category 2: Algebra > Inequalities > other
Category 3: Arithmetic > Fractions >

Explanation: a - b and b - a will never have the same sign, so the only way for the inequality in the question to be true is if a - b is negative, which means that b must be greater than a. In other words, the question can be rewritten as: Is b greater than a?

Statement (1) is sufficient, as it answers that question directly: b is greater than a. Statement (2) is insufficient: all it tells us is that the positive difference between the two variables is greater than 1. It contains no information about which variable is bigger. Choice (A) is correct.

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