A man can do a job in 15 days. His father takes 20 days and his son finishes it in 25 days. How long will they take to complete the job if they all work together?

16 men can complete a work in 35 days. In many days can 28 men complete the same piece of work?

24 men working 8 hours a day can finish a work in 10 days. Worked at the rate of 10 hours a day, the number of men required to finish the same work in 6 days is :

The average monthly income of A and B is Rs. 5050. The average monthly income of B and C is Rs. 6250 and the average monthly income of A and C is Rs. 5200. What is the monthly income of A?

If 80 lamps can be lighted, 5 hours per day for 10 days for Rs. 21,25, then the number of lamps, which can be lighted 4 hours daily for 30 days, for Rs. 76.50, is:

A person works on a project and completes 5/8 of the job in 10 days. At this rate, how many more days will he it take to finish the job?

10 men, working 6 hours a day can complete a work in 18 days. How many hours a day must 15 men work to complete the same work in 12 days?

x men working x hours per day can do x units of a work in x days. How much work can be completed by y men working y hours per day in y days?

If 18 binders bind 900 books in 10 days, how many  binders will be required to bind 660 books in 12 days?

A tank is filled in 5 hours by theree pipes A, B and C. The pipe C is twice as fast as B and B is twice as fast as A. How much time will pipe A alone take to fill the tank ?