The incomes of A, B, and C are in the ratio 7 : 9 : 12 and their expenditures are in the ratio 8 : 9 : 15. If A saves 1/4th of his income, find the ratio of their savings.
The ratio of land to water for the whole earth is 1 : 2 and for the Northern Hemisphere, it is 2 : 3. What is the ratio of land to water in the Southern Hemisphere?
The ratio of students in three classes is 2 : 3 : 5. If 20 students are increased in each class, the ratio becomes 4 : 5 : 7. Find the total number of students before the increase.
A mixture contains milk and water in the ratio 4 : 3. If 5 liters of water is added, the ratio becomes 4 : 5. Find the quantity of milk in the mixture.