26.A does a work in 10 days and B does the same work in 15 days. In how many days they together will do the same work?
A. 5 days B. 6 days
C. 8 days D. 9 days
Answer:
A's 1 day's work = 1/10
and B's 1 day's work = 1/15.
(A+B)'s 1 day's work = (1/10+1/15)
