Official Guide Explanation:
Data Sufficiency #9




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Solution and Metadata

Question: 9
Page: 273
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Ratio and Proportion >
Category 2: Word Problems > Other >

Explanation: To answer the question, we'll need to establish the relationship between how many Pat earned and how much he saved.

Statement (1) is sufficient. If Pat's earnings were x, he spent (1/2)x on living expenses, leaving a remainder of (1/2)x. If he saved (1/3) of that remainder, he saved (1/3)((1/2)x) = (1/6)x. Thus, (1/6)x = 600, so x = 3,600.

Statement (2) is insufficient. If he paid twice as much in taxes as he saved, he paid $1200 in taxes, but we don't know how that amount relates to the amount he earned. Choice (A) is correct.

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