Question
A is twice as efficient as B and can finish a piece of
work in 20 days less than B. B can finish this work in how many days?Solution
Ratio of efficiency of A and B = 2: 1 A will take 1/2 of time as compared to B. Say, B takes 2x days and A takes x days. ∴ 2x – x = 20 ⇒ x = 20 ∴ B takes 20 × 2 = 40 days to do the work.
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