A container has capacity of 240 litres filled with pure milk from this 48 litre milk is taken out and replaced with water. This process is repeated two more times. Find the percentage reduction in quantity of milk.

Each operation removes 48L of the mixture and replaces it with water. After 1st operation: 192L milk remains (48L removed). After 2nd: milk proportion is 192/240 = 0.8, so 48L mixture contains 38.4L milk, leaving 153.6L. After 3rd: milk proportion is 153.6/240 = 0.64, so 48L contains 30.72L milk, leaving 122.88L. Reduction from 240L is 117.12L, which is 117.12/240 × 100 = 48.8%.