Find the rate of interest per year, if the interest charged for 8 months be `0*06` times of the money borrowed.

Answer

To find the rate of interest per year given that the interest charged for 8 months is `0.06` times the money borrowed, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Variables**:
- Let the principal amount be \( P \).
- The time period \( T \) is given as 8 months.

2. **Convert Time Period to Years**:
- Since the time period is given in months, we need to convert it to years.
- \( T = \frac{8}{12} \) years.
- Simplifying this gives \( T = \frac{2}{3} \) years.

3. **Express the Simple Interest**:
- The interest charged for 8 months is given as \( 0.06 \times P \).
- Therefore, the simple interest \( SI = 0.06P \).

4. **Use the Simple Interest Formula**:
- The formula for simple interest is:
\[ SI = \frac{P \times R \times T}{100} \]
- Where \( R \) is the rate of interest per year.

5. **Substitute the Known Values**:
- Substitute \( SI = 0.06P \), \( P = P \), and \( T = \frac{2}{3} \) into the formula:
\[ 0.06P = \frac{P \times R \times \frac{2}{3}}{100} \]

6. **Cancel Out \( P \)**:
- Since \( P \) is common on both sides, we can cancel it out (assuming \( P \neq 0 \)):
\[ 0.06 = \frac{R \times \frac{2}{3}}{100} \]

7. **Rearranging the Equation**:
- Multiply both sides by 100:
\[ 6 = R \times \frac{2}{3} \]

8. **Solve for \( R \)**:
- Multiply both sides by \( \frac{3}{2} \):
\[ R = 6 \times \frac{3}{2} = 9 \]

9. **Conclusion**:
- Therefore, the rate of interest \( R \) is \( 9\% \) per year.

### Final Answer:
The rate of interest per year is **9%**.