Chain Rule Questions and Answers

If 18 pumps can raise 2170 tonnes of water in 10 days, working 7 hours a day ; in how many days will 16 pumps raise 1736 tonnes of water, working 9 hours a day ?

If 9 examiners can examine a certain number of answer books in 12 days by working 5 hours a day ; for how many hours a day would 4 examiners have to work in order to examine twice the number of answer books in 30 days ?

A rope makes 70 rounds of the circumference of a cylinder whose radius of the base is 14 cm. How many times can it go round a cylinder with radius 20 cm ?

If 3/5 of a cistern is filled in 1 minute, how much more time will be required to fill the rest of it ?

Ten pipes through which water flows at the same rate can fill a tank in 28 minutes. If three pipes go out of order, how long will the remaining pipes take to fill the tank ?

If 21 cows eat that much as 15 buffaloes, how many cows will eat that much as 105 buffaloes ?

A garrrison of 500 men had provisions for 27 days. After 3 days, a reinforcement of 300 men arrived. The remaining food will now last for how many days ?

A garrison had privisions for a certain number of days. After 10 days 1/5th of the men desert and it is found that the provisions will now last just as before. How long was that ?

If a certain number of workmen can do a piece of work in 25 days, in what time will another set of an equal number of men do a piece of work twice as great, suppsing that 2 men of the first set can do as much work in an hour as 3 men of the second set can do in an hour ?

15 men take 21 days of 8 hours each to do a piece of work. How many days of 6 hours each would 21 women take, if 3 women doa s much work as 2 men ?