Noun Summary

Two pipes A and B can fill a cistern in \(12\frac{1}{2} \) hours and 25 hours, respectively. The pipes are opened simultaneously and it is found that due to a leakage in the bottom, it took 1 hour 40 minutes more to fill the cistern. When the cistern is full, in how much time will the leak empty the cistern?

A man, a woman and a boy can complete a work in 3, 4 and 12 days, respectively. How many boys must assist one man and one woman to complete the same work in one day?

If 4 men and 6 boys can do a work in 8 days and 6 men and 4 boys can do the same work in 7 days, then how many days will 5 men and 4 boys take to do the same work?

A contract is to be completed in 75 days and 187 men are to work 15 hours per day. After 65 days, \(3\over5\) of the work is completed. How many additional men should be employed, so that the work is completed in time, each man now working 17 hours per day?