A container holds 20 liters of a milk and water mixture in the ratio 3:2. Ten liters of this mixture are taken out and replaced with an equal amount of pure milk. If this replacement process is done once again, what will be the final ratio of milk to water in the mixture?

Explanation

Initially, the mixture contains 12 liters of milk and 8 liters of water (3/5 of 20 liters is milk). Removing 10 liters removes 6 liters of milk and 4 liters of water. Remaining quantities are 6 liters milk and 4 liters water. Adding 10 liters of pure milk increases milk to 16 liters, making the ratio 16:4 or 4:1. Repeating the process, 10 liters are removed again, which contains 8 liters milk (4/5 of 10) and 2 liters water. Remaining milk is 8 liters and water is 2 liters. Adding 10 liters of pure milk again results in 18 liters milk and 2 liters water, giving a final ratio of 9:1.