A can do a work in 25 days and B can do it in 10 days. In how many days A and B can do the work? Choose the correct choice.
A) 20 days  B) 10 days  C) 6 8/7days  D) 8 days  E) 7 days
Explanation:   A's 1day's work = 1/25   B's 1day's work = 1/10   They work together = 1/25 + 1/10 = 7/50 = 50/7 = 6 8/7days   Answer: Option 6 8/7days
<result>C</result>
A can do a work in 25 days and B can do it in 10 days. In how many days A and B can do the work?