Official Guide Explanation:
Data Sufficiency #20




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Solution and Metadata

Question: 20
Page: 274
Difficulty: 4 (Moderately Easy)
Category 1: Geometry > Triangles > other

Explanation: In any given triangle, the angle opposite the longest side has the greatest degree measure. So, in order to know which angle is the largest, you must know which side is the longest. Since QR = x + 2 and PQ = x, QR must be greater than PQ, but it isn't clear how PR fits in.

Statement (1) clarifies PR: it's x + 3, so PR is greater than both QR and PQ. Thus, the angle opposite PR--angle Q--is the biggest. Statement (2) is not sufficient, as it says nothing about the relationship between x and y. Thus, the correct choice is (A).

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