A and B can complete a piece of work in 18 days and 12 days, respectively. They work on alternate days till the work gets completed. How long (in days) would it take A and B to complete the work, starting with A on the first day?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 14.5 days.
A can finish the work = 18 days
B can finish the work = 12 days
Total work = LCM of 18 and 12 = 72
Efficiency of A = 72/18 = 4
B = 72/12 = 6
2 days work done by A and B = 10
14 days work done by A and B = (4 + 6) × 7 = 70
Time taken by A to complete the remaining work A = (72 - 70)/4 = 0.5 day
Total days = 14 + 0.5 = 14.5 day