Use the compound interest formulas A=P (1+r/n)^nt and A =Pe^rt to solve the problem given. Round answers to the nearest cent.

Find the accumulated value of an investment of $20,000 for 6 years at an interest rate of 7% if the money is a.
compounded semiannually; b. compounded quarterly; c. compounded monthly; d. compounded continuously.

a. What is the accumulated value if the money is compounded semiannually?

$ blank (Round your answer to the nearest cent. Do not include the $ symbol in your answer.)

1 answer

To calculate the accumulated value of an investment using the compound interest formulas, we will use:

  1. For semiannual compounding: \[ A = P \left(1 + \frac{r}{n}\right)^{nt} \] where:
    • \( P = 20000 \) (the principal)
    • \( r = 0.07 \) (the annual interest rate in decimal)
    • \( n = 2 \) (the number of times interest is compounded per year)
    • \( t = 6 \) (the number of years)

Substituting in the values for semiannual compounding:

\[ A = 20000 \left(1 + \frac{0.07}{2}\right)^{2 \times 6} \] \[ A = 20000 \left(1 + 0.035\right)^{12} \] \[ A = 20000 \left(1.035\right)^{12} \]

Now we calculate \( (1.035)^{12} \):

\[ (1.035)^{12} \approx 1.491825 \]

Now we multiply by the principal:

\[ A \approx 20000 \times 1.491825 \approx 29836.50 \]

So the accumulated value if the money is compounded semiannually is:

\[ \boxed{29836.50} \]