10. 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 do as much work as 2 men ?

11. On a scale of a map 0.8 cm. represents 8.8 km. If the distance between two points on the map is 80.5 cm., the distance between these points is approximately :

12. If the rent for grazing 40 cows for 20 days is Rs. 370, how many cows can graze for 30 days on Rs. 111 ?