Official Guide Explanation:
Data Sufficiency #30




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Solution and Metadata

Question: 30
Page: 155
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Real Numbers >
Category 2: Algebra > Linear Equations-Two Unk >

Explanation: Statement (1) is sufficient. r, s, t, and u all must be between 1 and 9, since they are nonzero digits. The only set of nonzero digits that fulfills the equation r = 3s = 2t = 6u is r = 6, s = 2, t = 3, and u = 1, so x = 0.6231. Statement (2) is not sufficient: if ru = st, there are many possibilities, including the one that works in (1) as well as r = 2, u = 3, s = 1, and t = 6. Choice (A) is correct.

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