A container has a mixture of milk and water in the ratio 4:1. If ‘x’ liters of milk are added to the mixture, the ratio becomes 5:1, while ‘y’ liters of water are added, the ratio becomes 3:1. If the sum of x and y is 20 liters, then find the quantity of the original mixture.

Correct option is E

Information given:
A container has a mixture of milk and water in the ratio 4:1 ‘x’ liters of milk are added to the mixture, the ratio becomes 5:1
‘y’ liters of water are added, the ratio becomes 3:1
the sum of x and y is 20 liters
Explanation:
Let the milk and water in the container be ‘4a’ and ‘a’ liters respectively.
ATQ,

Equating (I) and (II);
x=3y
Given, x+y=20
3y+y=20
y=5
So, a=15
Required quantity=5a=75 liters