SBI PO – 2015 – 07

Question: A is twice as good a workman as B. Together they finish the work in 14 days. In how many days can it be done by each separately?                      [Ans. (a) A=21, B=42 days]

(a) 21, 42 days     (b) 42, 21 days     (c) 23, 21 days    (d) 12, 24 days   (e) None of these

Detailed explanation: A is twice as good a workman as B, so A = 2B

Since A + B can do a work in 14 days, so A + B = 2B + B = 3B can do it in 14 days.

Therefore, B alone can do the same work in 14*3 = 42 days.

Since A is twice efficient than that of B, so A will take half of the time taken by B. That is, half of 42 days = 21 days.

So, A can B can do the work in 21 days and 42 days respectively.