Official Guide Explanation:
Problem Solving #116




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Solution and Metadata

Question: 116
Page: 76
Difficulty: 6 (Moderately Difficult)
Category 1: Algebra > Equations >
Category 2: Arithmetic > Descriptive Statistics > Average

Explanation: Average, as always, is given by the sum of terms divided by the number of terms. In this case, that means total points divided by number of games. To find total points, start with the n games in which the team scored x points per game. The total number of points for those games is nx. In the last game, the team scored y points, so total points is nx + y . The number of games is given by the question as n + 1, so the average is ((points)/(games)) = ((nx + y)/(n + 1)), choice (A).

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