Correct Answer - Option 3 : 120
Given:
The mixture is of 120 liters
Alcohol ∶ Water = 2 ∶ 1
Calculation:
Let initial quantity of alcohol and water be 2x and 1x.
⇒ 2x + 1x = 120
⇒ 3x = 120
⇒ x = 40
Initial quantity of alcohol = 2x
⇒ 80 litres
Initial quantity of water = 1x
⇒ 40 litres
Let the water to be added be x litres.
80/(40 + x) = 2/3
⇒ 240 = 80 + 2x
⇒ x = 80
Quantity of water in the newly made mixture = 40 + 80 = 120
∴ Required answer is 120 liters