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?  Select:	A) 2 days	B) 6 days	C) 5 days	D) 7 days	E) 1 days
6 days   6 days   A's 1 day work = 1/10; 6 days's 1 day work = 1/15   (A + 6 days)'s 1 day work = (1/10 + 1/15) = 1/6   So, both together will finish the work in 6 days.
<result>B</result>
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?