Official Guide Explanation:
Data Sufficiency #112




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Solution and Metadata

Question: 112
Page: 161
Difficulty: 6 (Moderately Difficult)
Category 1: Arithmetic > Properties of Integers > Other
Category 2: Arithmetic > Descriptive Statistics > other
Category 3: Arithmetic > Descriptive Statistics > Average

Explanation: This question is much easier if you know one simple rule: if the numbers in a set are equally spaced--for instance, they are consecutive integers, consecutive even integers, or consecutive multiples of 7--the median is equal to the mean.

Statement (1), then, is sufficient: the numbers are equally spaced, so the mean and the median are the same. Statement (2) is insufficient: knowing the range indicates nothing about the specific spacing between the numbers. For instance, if n = 3, the range is 4. The set could be {0, 2, 4}, in which case the answer is "yes." The set could also be {0, 0, 4}, in which case the answer is "no."

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