A and B are solutions of acid and water. The ratio of water and acid in A and B are 4 : 5 and 1 : 2, respectively. If x liters of A is mixed with y liters of B, then the ratio of water and cid in the mixture becomes 8 : 13. What is x:y?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 3 : 4
Concept
Ratio
Application
Ratio of water and acid in A = 4 ∶ 5
Ratio of water and acid in B = 3 ∶ 6
Ratio of water and acid in the mixture = (4x + 3y)/(5x + 6y)
⇒ (4x + 3y)/(5x + 6y) = 8/13
⇒ 52x + 39y = 40x + 48y
⇒ 12x = 9y
⇒ x/y = 9/12
⇒ x/y = 3/4
Using Alligation Method
Let's take the quantity of water in different mixtures
Mixture A Mixture B
4/ 9 1 / 3
Resultant Quantity
8 / 21
Using Alligation Method, upon solving, we will get 3 : 4 = x : y