Correct Answer  Option 1 : 80
Given:
Volume of vessel = 95 litres
Ratio

Milk ∶ Water

Old

12 ∶ 7

New

4 ∶ 1

Calculation:
According to the question,
The initial quantity of Milk = (12/19) × 95 litres
⇒ 60 litres
and Initial quantity of water = (7/19) × 95 litres
⇒ 35 litres
Let the quantity of Milk added be x litres
Again according to the question,
Now, [(60 + x)/35] = (4/1)
⇒ 60 + x = 140
⇒ x = 80 litres
∴ 80 litres of milk is added to have the ratio 4 ∶ 1