Question

A can finish a work in 10 days and b does the same work in 15 days. In how many days they will do the same work together

Answer 1

both together can do work in= 10×15/10+15
=150/125
=6
togetherly they can do work in 6 days

Answer 2

Firstly we will find 1 day work of both A and B, then by adding we can get collective days for them,

So,

A's 1 day work = 1/10

B's 1 day work = 1/15

(A+B)'s 1 day work =

(110+115)=(3+230)=16