Question
βDβ can type a document in 45 days, but βDβ and
βEβ together can do it in 27 days. If βEβ worked for 15 days alone and then left, in how many days will βDβ finish the rest?Solution
ATQ,
Let total work = 135 {L.C.M of 45 and 27}
Efficiency of βDβ = 135 Γ· 45 = 3 units/day
Combined efficiency of βDβ and βEβ = 135 Γ· 27 = 5 units/day
So, efficiency of βEβ = 5 β 3 = 2 units/day
Work done by βEβ in 15 days = 2 Γ 15 = 30 units
Remaining work = 135 β 30 = 105 units
Time taken by βDβ = 105 Γ· 3 = 35 days
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