Correct Answer - Option 1 : 1

∶ 1

**Given:**

The ratio of milk and water be 2x and x and total amount of mixture is 15 liters

**Calculation:**

Let the amount of milk and water be 2x and x

According to the question, we have

2x + x = 15 liters

⇒ 3x = 15 liters

⇒ x = 5 liters

So, the amount of milk = 2x = (2 × 5) liters = 10 liters

And, amount of water = x = 5 liters

Now, 5 liters of water is further added to the mixture

So, total amount of water = (5 + 5) liters = 10 liters

Then, the ratio of milk and water = 10 ∶ 10 = 1 ∶ 1

**∴ The required ratio be 1 **∶** 1.**