A, B and C can do a work in 7 days, 8 days and 12 days respectively. In how many days can all three of them working together, complete the work? Choose the correct choice.
A) 2 50/59  B) 2 5/59  C) 2 2/50  D) 2 2/59  E) 2 1/59
Work done by all three of them in one day = 1/7 + 1/8 + 1/12 = 59/168   The number of days required = 168/59 = 2 50/59 days.   2 50/59nswer:2 50/59
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A, B and C can do a work in 7 days, 8 days and 12 days respectively. In how many days can all three of them working together, complete the work?