Question

the equation, $a = 2400(1+\frac{0.031}{4})^{4t}$, represents the amount of money earned on a compound interest savings account. what does the value 0.031 represent?
the value 0.031 represents the interest rate, which means the annual compounded interest rate is 3.1%.
the value 0.031 represents the interest rate, which means the annual compounded interest rate is 0.31%.
the value 0.031 represents the investment period, which means the investment is invested for 0.031 years.
the value 0.031 represents the investment period, which means the investment is invested for 3.1 years.

Explanation:

In the compound - interest formula $A = P(1+\frac{r}{n})^{nt}$, where $r$ is the annual interest rate. Here, the given formula is $A = 2400(1+\frac{0.031}{4})^{4t}$. Comparing with the standard formula, 0.031 is the annual interest rate. To convert a decimal to a percentage, we multiply by 100. So $0.031\times100 = 3.1\%$.

Answer:

The value 0.031 represents the interest rate, which means the annual compounded interest rate is 3.1%.