Question
A can complete a work in 40 days. B takes 20 days less
than A to complete the same work. In how many days can both of them together complete 90% of the work together?Solution
Time taken by B to complete the work = 40 – 20 = 20 days Let the total work = 40 units Efficiency of A = 40/40 = 1 units/day Efficiency of B = 40/20 = 2 units/day Required time taken = 0.90 x 40/(1+2) = 12 days
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