Tessa puts $8,000.00 into an account to use for school expenses. The account earns 7% interest, compounded continuously. How much will be in the account after 4 years?

Round your answer to the nearest cent.
$

1 answer

To calculate the amount in the account after 4 years with continuous compounding interest, you can use the formula:

\[ A = Pe^{rt} \]

where:

  • \( A \) is the amount of money accumulated after time \( t \),
  • \( P \) is the principal amount (the initial amount of money),
  • \( r \) is the annual interest rate (decimal),
  • \( t \) is the time the money is invested for (in years),
  • \( e \) is the base of the natural logarithm (approximately equal to 2.71828).

Given:

  • \( P = 8000 \) (the initial amount),
  • \( r = 0.07 \) (7% interest),
  • \( t = 4 \) (4 years).

Substituting the values into the formula, we get:

\[ A = 8000 \times e^{0.07 \times 4} \]

Calculating \( 0.07 \times 4 \):

\[ 0.07 \times 4 = 0.28 \]

Now, we calculate \( e^{0.28} \):

\[ e^{0.28} \approx 1.32313 \]

Now substitute back into the formula:

\[ A \approx 8000 \times 1.32313 \]

Calculating \( 8000 \times 1.32313 \):

\[ A \approx 10585.04 \]

Rounding to the nearest cent:

\[ A \approx 10585.04 \]

Therefore, the amount in the account after 4 years will be $10,585.04.