A and B together can do a piece of work in 12 days, while A alone can complete the same work in 18 days. How long will B alone take to complete the work?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 36 days.
Let total work = 36 ....... (Lcm of 12 and 18)
As we know , Efficiency × time taken = total work
Efficiency of A and B = 36/ 12 = 3
Efficiency of A = 36 /18 = 2
A + B = 3
2 + B = 3
B = 1 (efficiency)
Hence , B will take 36/1 = 36 days