A mixture containing 15% of acid is mixed with another mixture containing 85% of acid in the ratio x : y. If the quantity of acid in the final mixture is 29%, find the ratio x : y.

Correct Answer: 4 : 1
The ratio in which the liquids are mixed = x : y. X : y = (85 – 29) : (29 – 15) = 56 : 14 = 4 : 1