P and Q can do work separately in 10 and 20 days, respectively. In how many days can they finish it, working together?

A and B can do a work in 9 days and 12 days respectively. If they work on alternate days starting with A, then in how many days will the work be completed?

A can do a certain work in 12 days. B is 60% more efficient than A. How many days does B alone take to do the same work?

A, B and C can do some work in 40 days. A and C together can do twice as much work as B alone. Find the time taken by B to do the whole work.

A can do $\frac{1}{4}$th part of work in 12 days, B can do 50% work in 20 days , and C can do $\frac{1}{3}$rd of the same work in 15 days. Who complete the work first?

Vandana can do a piece of work in 25 days. Vasvi is 25% more efficient then Vandana. The number of days taken by Vasvi to do the same piece of work is:

A can do a work in 36 days, while B can do the same work in 48 days. If A works for x days while B works for x + 2 days, then one-third of the work is completed. Find the value of x?