When Martin was born, his father set up a $5,000 college fund for him with an annual compound interest rate of 7.3%. What is the total value of this account after 18 years, and what was the interest earned on the account? Round the answers to two decimal places. *Remember to use your STAAR Reference Sheet for support! (2 points) The final amount of the college fund is $ , and the amount of interest earned on the account is $.....

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1 answer

To calculate the total value of the college fund after 18 years with an initial amount of $5,000 and a compound interest rate of 7.3%, we can use the compound interest formula:

\[ A = P(1 + r)^n \]

Where:

  • \( A \) is the total amount after \( n \) years,
  • \( P \) is the principal amount (initial investment),
  • \( r \) is the annual interest rate (as a decimal),
  • \( n \) is the number of years the money is invested or borrowed.

Given:

  • \( P = 5000 \)
  • \( r = 7.3% = 0.073 \)
  • \( n = 18 \)

Substituting the values into the formula:

\[ A = 5000(1 + 0.073)^{18} \]

Calculating \( 1 + 0.073 \):

\[ 1 + 0.073 = 1.073 \]

Now calculating \( 1.073^{18} \):

\[ 1.073^{18} \approx 3.660583 \]

Now calculate \( A \):

\[ A \approx 5000 \times 3.660583 \approx 18302.915 \]

Rounding to two decimal places, the total amount in the account after 18 years is:

\[ A \approx 18302.92 \]

Next, we need to find the interest earned. The interest earned can be calculated as:

\[ \text{Interest} = A - P \]

Substituting the values:

\[ \text{Interest} = 18302.92 - 5000 = 13302.92 \]

Thus, rounding to two decimal places, the interest earned on the account is:

\[ \text{Interest} \approx 13302.92 \]

So, the final answers are:

  • The total value of the college fund is $18,302.92.
  • The amount of interest earned on the account is $13,302.92.