Question
A’ and ‘B’ together can complete a work in 15 days
while ‘A’ takes 20 days to complete the same work alone. If ‘C’ is 50% more efficient than ‘B’, then find the time taken by ‘C’ alone to complete the whole work.Solution
Let the total work = 60 units Efficiency of (A + B) = 60/15 = 4 units/day Efficiency of ‘A’ = 60/20 = 3 units/day Therefore, efficiency of ‘B’ = 4 – 3 = 1 unit/day Efficiency of ‘C’ = 1.5 × 1 = 1.5 units/day Required time taken = 60/1.5 = 40 days
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