Question
A child is half as efficient as a man. How much time do
8 children need to build a wall that is 60% the size of the wall built by the 12 men in 15 days?Solution
Let the efficiency of each man be '2x' units/daySo, total work = 2x X 12 X 15 = '360x' unitsAnd efficiency of a child = 2x ÷ 2 = 'x' units/daySo, required time = (360x X 0.6) ÷ (8 X x) = 27 days
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