Question
'A' can do some work alone in 16 days. 'A'and 'B' work
together for 8 days after which'A' leaves and 'B' finishes the remaining work alone in 12 days. How much time does 'B' need to finish the work alone?Solution
ATQ, Let the efficiency of 'A' be 'a' units/day. So, total work = 16 × a = '16a' units So, work done by 'A' in 8 days = a × 8 = '8a'units So, work done by 'B' = 16a - 8a = '8a' units So, efficiency of 'B' = 8a ÷ (12 + 8) = '0.4a'units/day So, required time = 16a ÷ 0.4a = 40 days
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