93.
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 ratio of water and acid in the mixture becomes 8 : 13. What is x : y?

94.
A drink of chocolate and milk contains 8% pure chocolate by volume. If 10 litres of pure milk are added to 50 litres of this drink, the percentage of chocolate in the new drink is: