A and B are solutions of acid and water. The ratios of water and acid in A and B are 4 : 5 and 1 : 2, respectively. If x litres of A is mixed with y litres of B, then the ratio of water and acid in the mixture becomes 8 : 13. What is x : y ?
Answer & explanation
Correct answer: option 3
Acid : Water : Total
A : 4 : 5 : 9 )× 7 = 63
B : 1 : 2 : 3 )× 21 = 63
New: 8 : 13 : 21 )× 3 = 63
Use alligation method on acid:
