Question
βRβ alone can build a wall in 40 days. Together,
βRβ and βSβ can do it in 25 days. If βSβ worked for 8 days alone and stopped, how many more days would βRβ need to complete the task?Solution
ATQ,
Let total work = 200 {L.C.M of 40 and 25}
Efficiency of βRβ = 200 Γ· 40 = 5 units/day
Combined efficiency of βRβ and βSβ = 200 Γ· 25 = 8 units/day
So, efficiency of βSβ alone = 8 β 5 = 3 units/day
Work done by βSβ in 8 days = 3 Γ 8 = 24 units
Remaining work = 200 β 24 = 176 units
Time taken by βRβ to finish remaining work = 176 Γ· 5 = 35.2 days
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