To do a certain work, the ratio of efficiency of A to that of B is 3:7. Working together, they can complete the work in 10.5 days. They work together for 8 days. 60% of the remaining work will be completed by A alone in ?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 ie 5 days.
Efficiency ratio of A : B = 3 : 7
Work by A in 1 day = 5 units
Work by B in 1 day = 7 units
Work remaining = (10.5 - 8 ) × 10 = 25 units
= (60/100) × 25 = 15 units
Time taken by A = 15/3 = 5 days