Question
'Ravi', 'Sohan', and 'Karan' can individually finish a task
in 45, 30, and 60 days, respectively. Sohan and Karan work together for ‘x’ days and then leave. Ravi completes the remaining work in 9 days. What is the value of ‘x’?Solution
ATQ,
Let the total work = L.C.M of 45, 30, and 60 = 180 units
Efficiency of Ravi = 180 ÷ 45 = 4 units/day
Efficiency of Sohan = 180 ÷ 30 = 6 units/day
Efficiency of Karan = 180 ÷ 60 = 3 units/day
Work done by Ravi in 9 days = 4 × 9 = 36 units
Work done by Sohan and Karan = 180 - 36 = 144 units
So, x = 144 ÷ (6 + 3) = 144 ÷ 9 = 16 days
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