A can complete a piece of work in 9 days. B and C can complete the same work in 12 days and 18 days, respectively. If A, B, and C work together, then in how many days will they complete the work?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 4.
Total work = 36 (LCM of 9, 12, and 18)
Efficiency of A, B, and C = (36/9) + (36/12) + (36/18) = 4 + 3 + 2 = 9 units/day
Time required for A, B, and C work together to finish the work = 36/9 = 4 days