Official Guide Explanation:
Problem Solving #63

Background

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Solution and Metadata

Question: 63
Page: 70
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Descriptive Statistics > Average
Category 2: Arithmetic > Descriptive Statistics > other

Explanation: To find the difference between the median and the mean, you first must find the median and the mean. To find the median, put the numbers in order: {0, 2, 4, 5, 8, 11}. There are an even number of terms, so the median is the mean of the middle two numbers, 4 and 5, or 4.5. Find the mean by dividing the sum of terms by the number of terms: ((0 + 2 + 4 + 5 + 8 + 11)/6) = (30/6) = 5. Since the mean is 5 and the median is 4.5, the mean is 5 - 4.5 = 0.5 greater than the median, choice (A).

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