Problem-Solving and Data Analysis practice question

Answer: B. 1

Mean = (5+8+8+10+14+15)/6 = 60/6 = 10. With six values, the median is the average of the 3rd and 4th: (8+10)/2 = 9. Difference = 10 − 9 = 1. The trap is taking a single middle value instead of averaging the two middles in an even-sized set.

Why the other answers are wrong

A. 0

You landed on a median of 10 by taking a single middle value; with six values the median is the average of the 3rd and 4th, (8 + 10)/2 = 9, so the difference from the mean of 10 is 1.

C. 2

You used 8, the 3rd value, as the median; in an even-sized set you average the two middle values: (8 + 10)/2 = 9, giving 10 − 9 = 1.

D. 3

No single slip in the mean or median produces 3 here — compute mean = 60/6 = 10 and median = (8 + 10)/2 = 9, and the difference is 1.

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