The ratio of students of three classes is 2:3:4. If 12 students are increased in each classes then their ratio turns into 8:11:14. What was the total number of students in all the three classes originally ?

The ratio of milk and water in 729 litre mixture is 7:2. To obtain a mixture in which the ratio of milk and water is 7:3, what will be the amount of extra water to be added in new mixture?