Question : X and Y together can do a work in 10 days. Y and Z together can do the same work in 15 days. Z and X together can do the same work in 12 days. In how many days can Z alone do the same work?

Question : X and Y together can do a piece of work in 30 days. Z alone can do it in 60 days. If they worked together, then in how many days they can finish the work?

Question : A and B together can do a piece of work in 24 days. A alone can do this work in 40 days. In how many days can B alone do this work?

Question : X alone can finish a work in 18 days, and Y alone can finish the same work in 9 days. If X, Y, and Z together can finish the same work in 4 days, then in how many days Z alone can finish the work?

Question : Seema alone can do a piece of work in 8 days and her sister Reema alone can do the same work in 24 days. If they worked together, then in how many days they will complete the work?