Question
A and B can do a work in 21 days, A is (7/4) times as
efficient as B. In how many days, A alone can complete the (100/3)% of the work?Solution
Let efficiency of B be 4 units/day Efficiency of A = 4 × (7/4) = 7 units/day We know, Total work = Efficiency × Time taken Total work = (7 + 4) × 21 = 231 units 100/3 % of the total work = 231 × 100/300 = 77 units A alone can complete 100/3 % of the work in = 77/7 = 11 days
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