Question

A can do a piece of work in 15 days while B can do it in 10 days. How long will they take together to do it ?​

Answer 1

A's 1 day work=1/15

B's 1 day work=1/10

A and B's 1 day work = 1/15 +1/10 =5/30 =1/6

They can do the work in 6 days