A and B can do a piece of work in 40 days and 30 days respectively. They worked together for 12 days after that B was replaced by C. the work finish in next 8 days. In how many days C can alone finish the work?

10 men can finish painting a wall in 8 days. How many more men will be needed if the painting work is to be finished in 4 days?

1200 soldiers in a fort had enough food for 28 days. After 4 days, some soldiers left the fort. Thus, food lasted for 32 more days. How many soldiers left?

Panu, Jiban and Jalil can complete a certain task individually in 30, 20 and 60 days, respectively. Jiban started work on the task and Panu and Jalil agreed to help Jiban on every third day. How many days will it take to complete the task?

A, B and C complete a work in 10, 12 and 15 days respectively. They started the work together. But A left the work before 5 days of its completion. B also left the work 2 days after A left. In how many days will the work completed? 

Sanjay and Jacob start running in opposite directions from the same point at speeds of 7m/s and 5m/s. After 42 minutes, how far would they be from each other?

6 carpenters make 96 windows in 16 days. If 8 carpenters work for 4 days how many windows will they make?

X, Y and Z take 18 days to complete a piece of work. If X works alone he finishes the work in 36 days and if Y works alone he finishes it in 60 days. How long will it take Z to complete the work alone?