Official Guide Explanation:
Data Sufficiency #85

Background

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Solution and Metadata

Question: 85
Page: 280
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Mixture Problems >
Category 2: Arithmetic > Ratio and Proportion >

Explanation: The question gives us the equation p + s = 100. Two variables, one linear equation, so we'll need another linear equation to solve for p, the number of tickets Paula sold.

Statement (1) is sufficient: it offers another linear equation, s = (2/3)p. It can be combined with the initial equation to find p. Statement (2) is not sufficient: the total number of tickets sold for Club X is a third variable, so it can't be related back to the initial equation. Thus, choice (A) is correct.

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