A and B can do a piece of work in 18 days. They worked together for 12 days and then B left. A finished the remaining work in 10 days. In how many days can A alone complete the work?
Show answer & explanation
Correct answer: A
Explanation
(A + B)'s 1-day work efficiency = 1/18
Work done in 12 days = 12/18 = 2/3
Remaining work = 1/3
A completed 1/3 of the work in 10 days.
Therefore, A's 1-day work efficiency = 1/30
A alone will complete the work in 30 days.