A can finish a work in 18 days and B can do the same work in 15 days. B worked for 10 days and left the job. In how many days, A alone can finish the remaining work

A and B together can finish a work in 16 days, while B can do the same work alone in 24 days. In how many days can A alone finish the work

A man does double the work done by a boy in the same time. The number of days that 3 men and 4 boys will take to finish a work which can be done by 10 men in 8 days is

P and Q can finish a work in 15 and 10 days respectively. Q starts the work and leaves it after 5 days. The number of days in which P can complete the work is :