Question
P, Q, R and S can do a piece of work in 20 days. If P
and Q together can do it in 50 days, and R alone in 60 days, then in how many days can S alone do it?Solution
Let, total work = LCM of (20, 50, and 60) = 300 Hence, Efficiency of (P + Q + R + S) = 15 Efficiency of (P + Q) = 6 Efficiency of R = 5 Efficiency of S = 15-6-5=4 S alone can complete the whole work in = 300/4 = 75 days.
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