Amit can do a piece of work in 4 days and Sumit can do it in 6 days How long will they take, if both Amit and Sumit work together ?

Raj can do a piece of work in 20 days and Rohan can do it in 12 days. How long will they take, if both work together?

A can do a piece of work in 4 days and B can do it in 12 days. In how many days will they finish the work, both working together ?

Anil can do a piece of work in 5 days and ankur in 4 days. How long will they take to do the same work, if they work together?

Anil can do a piece of work in 5 days and ankur in 4 days. How long will they take to do the same work, if they work together?

A can do a piece of work in 10 days and B can do the same work in 12 days. How long will they take to finish the work, if both work together?

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