A alone can do 110 part of a work in 8 hours. B alone can do 15 part of the same work in 4 hours. If they work together, then how many hours will they take to complete 916 part of the same work?

If P and Q together can complete a piece of work in 15 days and P alone can do it in 45 days, in how many days can Q alone complete that work?

A can lay a railway track between two stations in 16 days and B can do the same job in 12 days. With the help of C, they finished the job in 4 days. In how many days can C alone do the job?