The ratio of boys and girls in a school is 5:3. If there are 115 boys, find the number of girls in the school.

Answer

To solve the problem of finding the number of girls in a school where the ratio of boys to girls is 5:3 and there are 115 boys, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Ratio**: The ratio of boys to girls is given as 5:3. This means for every 5 boys, there are 3 girls.

2. **Set Up the Variables**: Let the number of boys be represented as \(5x\) and the number of girls as \(3x\), where \(x\) is a common multiplier.

3. **Use the Given Information**: According to the problem, the number of boys is 115. Therefore, we can set up the equation:
\[ 5x = 115 \]

4. **Solve for \(x\)**: To find the value of \(x\), divide both sides of the equation by 5:
\[ x = \frac{115}{5} \]
\[ x = 23 \]

5. **Calculate the Number of Girls**: Now that we have the value of \(x\), we can find the number of girls using the expression \(3x\):
\[ \text{Number of girls} = 3x = 3 \times 23 = 69 \]

6. **Conclusion**: Therefore, the number of girls in the school is 69.

### Final Answer:
The number of girls in the school is **69**.

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