Question
The average age of a group is 40 years. When two members
having an average age of 58 years leave the group, the average age drops by 3 years. What was the original number of people in the group?Solution
ATQ,
Let the number of people in the group initially be 'n'.
(40n - 2 Ă— 58) Ă· (n - 2) = 40 - 3
Or, 40n - 116 = 37n - 74
Or, 3n = 42
Or, n = 14
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