Question
A group of boys has an average weight of 44 kg. One boy
weighing 50 kg leaves the group and another boy weighing 40 kg joins the group. If now the average weight of group is 42 kg, then how many boys are there in the group?Solution
Let us assume the total boys in the group be 'b' The sum of the weight of the all-boys = 44b 42b = 44b - 50 + 40 42b = 44b - 10 44b - 42b = 10 2b = 10 b = 5
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