In a mixture of 60 litres, the ratio of milk and water is 2:1. If this ratio is to be 1: 2, then the quantity of water to be further added is:

Options

A. 20 litres
B. 30 litres
C. 40 litres
D. 60 litres

Answer

To solve the problem step by step, follow these instructions:

### Step 1: Understand the initial ratio of milk and water
The initial ratio of milk to water is given as 2:1. This means for every 2 parts of milk, there is 1 part of water.

### Step 2: Calculate the total parts in the mixture
The total parts in the mixture can be calculated as:
\[ 2 + 1 = 3 \text{ parts} \]

### Step 3: Determine the quantity of milk and water in the mixture
Given that the total volume of the mixture is 60 litres, we can find the quantity of milk and water:
- Quantity of milk:
\[ \text{Milk} = \frac{2}{3} \times 60 = 40 \text{ litres} \]
- Quantity of water:
\[ \text{Water} = \frac{1}{3} \times 60 = 20 \text{ litres} \]

### Step 4: Set up the new ratio requirement
We need to change the ratio of milk to water to 1:2. This means for every 1 part of milk, there should be 2 parts of water.

### Step 5: Calculate the required quantity of water for the new ratio
Let the quantity of water in the new mixture be \( W \). According to the new ratio:
- If the quantity of milk is 40 litres, then the quantity of water should be:
\[ W = 2 \times \text{Milk} = 2 \times 40 = 80 \text{ litres} \]

### Step 6: Find the additional quantity of water needed
We initially have 20 litres of water. To find out how much more water is needed, we subtract the initial quantity of water from the required quantity:
\[ \text{Additional Water} = 80 - 20 = 60 \text{ litres} \]

### Conclusion
The quantity of water to be further added is **60 litres**.

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