A mixture containing 60% of milk is mixed with another mixture containing 75% of milk in a ratio x : y. If the quantity of milk in the final mixture is 69%, find the ratio x : y.

Correct Answer: 2 : 3
The ratio in which the liquids are mixed = x : y. X : y = (75 – 69) : (69 – 60) = 6 : 9 = 2 : 3