Official Guide Explanation:
Data Sufficiency #69




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Solution and Metadata

Question: 69
Page: 278
Difficulty: 5 (Moderate)
Category 1: Algebra > Inequalities > Negatives
Category 2: Algebra > Absolute Value >

Explanation: While the number may not be drawn to scale, we can trust that the variables are in the right order, so q < rStatement (1) is sufficient. It tells us that q and s have the same absolute value--they are the same distance from zero, only in opposite directions. For instance, if q= - 3, s = 3. Since r is in between q and s, it is closer to zero than either of them. And because t must be greater than s (and thus, further from zero), r is the closest to zero of all four.

Statement (2) is insufficient. The inequality tells us that t is further from zero than q--for instance, if q= - 2, t must be greater than 2 in order for -t to be less than -2. Consider a couple of different acceptable sets of values:

q= - 2, r = 3, s = 4, t = 5

q= - 2, r = 1, s = 4, t = 5

Both follow the rules in the question and (2), but give contradictory answers. Choice (A) is correct.

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