Chain Rule - Questions and Answers

11. If 17 labourers can dig a ditch 26 metres long in 18 days, working 8 hours a day, how many more labourers should be engaged to dig a similar ditch 39 metres long in 6 days, each labourer working 9 hours a day ?

12. 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, supposing that 2 of the first set can do as much work in an hour as 3 of the second set can do in an hour ?

13. A contract is to be completed in 56 days and 104 men were set to work, each working 8 hours a day. After 30 days, of the work is completed. How many additional men may be employed, so that the work may be compeleted in time, each man now working 9 hours a day ?

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

15. 2 men and 7 boys can do piece of work in 14 days; 3 men and 8 boys can do the same in 11 days. 8 men and 6 boys can do 3 times the amount of this work in :