Question
‘A’ and ‘B’ can do a piece of work in 20 days
and 25 days, respectively. If they started the work together and worked on it for 4 days, then find the time taken by ‘B’ alone to complete the remaining work.Solution
Let total amount of work be 100 units Efficiency of ‘A’ = 100/20 = 5 units/day Efficiency of ‘B’ = 100/25 = 4 units/day Amount of work done by ‘A’ and ‘B’ together in 4 days = (5 + 4) × 4 = 36 units Time taken by B to complete remaining work = (100 – 36)/4 = 16 days
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