A alone can complete a work in 18 days and B alone in 14 days. Starting with A, they work on alternate days. The total work will be completed in:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 15 days.
Total work = LCM of 18 and 14 = 126
Efficiency of A = 126/18 = 7
Efficiency of B = 126/14 = 9
2 days work of A and B = 7 + 9 = 16
Work done in 14 days = 16 × 7 = 112
Work done on 15th day by A = 7
Remaining work = 126 - 112 - 7 = 7
Time required for B to complete the remaining work = 7/9 days
Total time = 15 + (7/9) = 15 days