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?
Options:
(A) 1
(B) 6
(C) 7
(D) 5
(E) 43 Now, let's think a bit. Some random thoughts:
A's 1 day work = 1/10; B's 1 day work = 1/15
(A + B)'s 1 day work = (1/10 + 1/15) = 1/6
So, both together will finish the work in 6 days.
The final answer: (B).