Question

    A man is 60% more efficient than a boy. Together, two

    boys and one man can finish a task in 15 days. How many boys would be needed to complete the same task in 13.5 days?
    A 6 Correct Answer Incorrect Answer
    B 5 Correct Answer Incorrect Answer
    C 4 Correct Answer Incorrect Answer
    D 3 Correct Answer Incorrect Answer

    Solution

    Let the efficiency of a boy = '5x' units/dayThen, efficiency of a man = 5x X 1.6 = '8x' units/daySo, combined efficiency of 2 boys and 1 man = 5x X 2 + 8x = '18x' units/daySo, total work = 18x X 15 = 270x unitsSo, number of boys required to complete the work in 13.5 days = (270x ÷ 13.5) ÷ 5x = 4

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