Question
It takes A and B, 3 and 6 hours, respectively, to
complete a certain work. If they work on the alternate hour. How long will it take them to accomplish the task?Solution
Total work = LCM (3, 6) = 6 Efficiency of A = 2 Efficiency of B = 1 Since they work on alternate days starting with A, So, 2 hours = 3 units Now to complete 6 units of work 2 x 2 hours = 3 x 2 units 4 hours = 6 units Answer is 4 hours.
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