Question
βAβ alone can complete a work in 10 days. βBβ
alone can complete the same work in 20 days. If βAβ and βBβ work together for 3 days, then the remaining work can be completed by βAβ alone in how many days?Solution
Let the total amount of work = 20 units {LCM of 10 and 20} Then, efficiency of βAβ = 20/10 = 2 units/day Efficiency of βBβ = 20/20 = 1 units/day Combined efficiency of βAβ and βBβ = 2 + 1 = 3 units/day Work completed by βAβ and βBβ together in 3 days = 3 Γ 3 = 9 units Remaining work = 20 β 9 = 11 units Time taken by βAβ alone to complete the remaining work = 11/2 = 5.5 days
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