Official Guide Explanation:
Data Sufficiency #115




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Solution and Metadata

Question: 115
Page: 283
Difficulty: 6 (Moderately Difficult)
Category 1: Algebra > Symbolism >
Category 2: Algebra > Functions > other

Explanation: As usual, when the GMAT introduces a complicated - sounding rule or function, it represents something quite simple. The two functions result in either the larger of the two numbers in parentheses (max) or the smaller (min). We're looking for min(10,w). If w is greater than 10, the result is 10. If w is less than 10, the result is w, and we'll need to know the value of w to answer the question.

Statement (1) is sufficient. In plain English, w is equal to the greater of 20 and z. If z is less than 20, the greater of 20 and z is 20. If z is greater, z must be larger than 20. In other words, w is either 20 or something greater than 20. Thus, min(10,w) = 10, because w must be greater than 10.

Statement (2) is also sufficient. Following the same reasoning as in (1), if w= max(10,w), w must be greater than 10. If w is greater than 10, min(10,w) = 10. Choice (D) is correct.

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