Correct Answer  Option 3 : 460
Given:
In a mixture of 140 liters, the ratio of milk and water 6: 1. If this ratio is to be 1: 4
Calculation
Quantity of milk =


140 x

6

Liters = 120 liters

7

Quantity of water in it = (140 – 120) liters = 20 liters
New ratio = 1: 4
Let the quantity of water to be added further be x liters
Then, milk: water = 120 ÷ (20 + x)




Then, 120 ÷ (20 + x) = 1 ÷ 4
20 + x = 480
x = 460
Therefore, Quantity of water to be added = 460 liters