The ratio of efficiencies of A and B is 9 : 7. Working together, they can complete a certain work in 514 days. A alone completed 37 part of the work and B alone completed the remaining work. The total number of days in which the entire work got completed is:

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?