A can complete 4/5 part of a work in 10 days. B is 5 times as efficient as A. In how many days will B alone complete the same work?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 2.5 days.
A can complete 4/5 part of a work in 10 days
A's work rate = (4/5)/10 = 2/25 work per day
B's work rate = 5 × A's work rate
B's work rate = 5 × 2/25 = 2/5 work per day
Time taken by B = 5/2 = 2.5 days