In a mixture of 45 litres the ratio of milk to water is 4:1. Additional 9 litres of water is added to the mixture. Find the ratio of milk to water in the resulting mixture.
Pick:
A) 2 / 1	B) 4 / 1	C) 2 / 3	D) 3 / 4	E) 3 / 2

Rationale: "given that milk / water = 4 x / x and 4 x + x = 45 - - > x = 9 . thus milk = 4 x = 36 liters and water = x = 9 liters . new ratio = 36 / ( 9 + 9 ) = 36 / 18 = 2 / 1 . answer : a ."
Answer: A