Official Guide Explanation:
Data Sufficiency #35




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Solution and Metadata

Question: 35
Page: 155
Difficulty: 5 (Moderate)
Category 1: Algebra > Linear Equations-Two Unk >
Category 2: Arithmetic > Properties of Integers > Other

Explanation: Given one linear equation with two variables, you need a second linear equation with the same two variables to find the value of the variables. Statement (1) is insufficient: it doesn't provide specific values. Statement (2) is sufficient: either w - 2 = z or z - 2 = w. In either case, because w + z = 28, one of the variables is 13 and the other is 15. Regardless of which is which, the product is (13)(15). Choice (B) is correct.

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