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Problem of the Week
Problem E
Just an Average Sum

Faisal chooses four numbers. When each number is added to the mean (average) of the other three, the following sums are obtained: \(25\), \(37\), \(43\), and \(51\).

Determine the mean of the four numbers Faisal chose.

Extra Problem: Can you interpret the following picture puzzle? You may need to research the meanings of some mathematical symbols used in the puzzle.

An inequality showing that capital B is greater than a mathematical expression. The mathematical expression consists of a capital greek letter Sigma with the equality i=1 below it and the variable n on top of it. To the left of the letter Sigma there is the fraction 1 over n.  To the right of the sigma there is the term x subscript i.