Official Guide Explanation:
Data Sufficiency #131




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Solution and Metadata

Question: 131
Page: 284
Difficulty: 5 (Moderate)
Category 1: Algebra > Linear Equations-Two Unk >
Category 2: Word Problems > Mixture Problems >

Explanation: The information in the question tells us that h = t + 4, where h is the number of heads that resulted from a certain number of coin flips, and t is the number of tails that resulted. To find the value of h, we'd need another linear equation to go along with the first one.

Statement (1) is sufficient: it says that h + t = 24. Combined with h = t + 4, that's two linear equations and two variables, so we can solve for h. Statement (2) is more convoluted, but also sufficient. Setting up an equation for total points looks like this: 3h + t = 52, another linear equation with two variables that we can pair with the initial equation. The correct choice is (D).

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