C can do a work in 12 days, and D can do the same work in 18 days. If they work together for 6 days,

A. 1/3

B. 1/4

C. 1/2

D. 1/6

E. None of the above

Answer: A. 1/3

C and D together can complete 1/12 + 1/18 = 5/36 of the work in one day. In 6 days, they complete 5/6 of the work, leaving 1/6.

Posted in: Time & Work - Aptitude - Mathematics