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    Question

    Worker 'A' can complete the entire task in 35 hours, and

    Worker 'B' can complete it in 40 hours, when working individually. If both 'A' and 'B' work together, how much time will it take for them to finish 60% of the task?
    A 13.2 hours Correct Answer Incorrect Answer
    B 11.2 hours Correct Answer Incorrect Answer
    C 9.6 hours Correct Answer Incorrect Answer
    D 16 hours Correct Answer Incorrect Answer

    Solution

    Let the total work = L.C.M of 35 and 40 = 280 units Then, efficiency of 'A' = 280 ÷ 35 = 8 units/hour Efficiency of 'B' = 280 ÷ 40 = 7 units/hour 60% of the work = 280 X 0.6 = 168 units Time taken by 'A' and 'B' working together to complete 60% of the work = 168 ÷ (7 + 8) = 11.2 hours

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