13. If 27 kg. of corn would feed 42 horses for 21 days, in how many days would 36 kg. of it feed 21 horses ?

14. 120 men had provisions for 200 days. After 5 days, 30 men died due to an epidemic. The remaining food will last for ?

15. If 9 men working 7 hours a day can finish a work in 20 days; then how many days will be taken by 12 men, working 6 hours a day to finish the work; it being given that 3 men of latter type work as much as 2 men of the former type in the same time ?