Ravi can do a piece of work in 25 days while Prakash can do it in 40 days. In how many days will they finish it together?  Choose the correct choice from the following answers
A) 15 5/13 days
B) 16 1/13 days
C) 17 1/13 days
D) 17 7/15 days
E) 18 1/13 days
1/25 + 1/40 = 13/200   200/13   = 15 5/13 days   15 5/13 daysnswer: 15 5/13 days
<result>A</result>
Ravi can do a piece of work in 25 days while Prakash can do it in 40 days. In how many days will they finish it together?