Pipe A and Pipe B can fill a cistern together in x hours. The efficiency of A is 40% less than the efficiency of B. If B can fill 512th of the cistern in 114 hours, find the value of x.

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?