Explanation:
To calculate the monthly interest rate from an annual interest rate, divide the annual interest rate by 12 (the number of months in a year). Here's the formula:
![\[ \text{Monthly Interest Rate} = \frac{\text{Annual Interest Rate}}{12} \]](https://img.qammunity.org/2024/formulas/business/high-school/bc41gfkfumcnoy0jqvgk90moclooidiw0q.png)
For example, if the annual interest rate is 5%, the monthly interest rate would be:
![\[ \text{Monthly Interest Rate} = (0.05)/(12) = 0.0041667 \]](https://img.qammunity.org/2024/formulas/mathematics/college/87a1twr04qh2hyct4hoqchdhbdt4t1v5gl.png)
Rounded to four decimal places, the monthly interest rate is approximately 0.0042, or 0.42%.