Question
Ramesh and Rahman can do a work in 20 and 25 days
respectively. After doing collectively 10 days of work, they leave the work due to illness and Suresh completes rest of the work in 3 days. How many days Suresh alone can take to complete the whole work ?Solution
Ramesh               Rahmaan 20                         25               100 5                           4 Total work =100 Work done by Ramesh and Rahman in 10 days = (5 + 4) x 10 = 90 Remaining work = 100-90 = 10 Let the efficiency of Suresh be x, then = 3x = 10 = x = 10/3 Suresh complete the whole work in = 100/(10/3) = 10 x 3 = 30 days
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