A and B can do a certain work in 2212 days and 30 days, respectively. They started the work together but after 6 days, B had to leave. Then, A worked with C and completed the remaining work in 3 days. C alone can complete the original work in:

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?