A mixture of alcohol and water contains 7% alcohol. How much mixture (in litres) is required to get 357 litres of alcohol?

Options

A. 6300
B. 4200
C. 4900
D. 5100

Answer

To solve the problem of how much mixture is required to obtain 357 liters of alcohol when the mixture contains 7% alcohol, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of the Mixture:**
The mixture contains 7% alcohol. This means that in every 1 liter of the mixture, there are 0.07 liters of alcohol.

2. **Set Up the Equation:**
Let \( x \) be the amount of mixture (in liters) needed to obtain 357 liters of alcohol. Since 7% of the mixture is alcohol, we can express this relationship as:
\[ 0.07x = 357 \]

3. **Solve for \( x \):**
To find \( x \), we need to isolate it in the equation. We can do this by dividing both sides of the equation by 0.07:
\[ x = \frac{357}{0.07} \]

4. **Calculate \( x \):**
Now, we perform the division:
\[ x = \frac{357}{0.07} = 5100 \]

5. **Conclusion:**
Therefore, the amount of mixture required to get 357 liters of alcohol is 5100 liters.

### Final Answer:
The required amount of mixture is **5100 liters**.

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