Questions: Arianna invests 5500 in a new savings account which earns 5.6% annual interest, compounded continuously. What will be the value of her investment after 7 years? Round to the nearest cent.
Transcript text: Arianna invests $\$ 5500$ in a new savings account which earns $5.6 \%$ annual interest, compounded continuously. What will be the value of her investment after 7 years? Round to the nearest cent.
Interest formulas
Solution
Solution Steps
Step 1: Identify the Variables
We are given the following values for the investment:
Principal amount \( P = 5500 \)
Annual interest rate \( r = 5.6\% = 0.056 \)
Time in years \( t = 7 \)
Step 2: Apply the Continuous Compounding Formula
To find the future value \( A \) of the investment, we use the formula for continuous compounding:
\[
A = Pe^{rt}
\]
Substituting the known values:
\[
A = 5500 \cdot e^{0.056 \cdot 7}
\]
Step 3: Calculate the Exponential Component
First, we calculate the exponent:
\[
rt = 0.056 \cdot 7 = 0.392
\]
Now, we compute \( e^{0.392} \):
\[
e^{0.392} \approx 1.478
\]
Step 4: Calculate the Future Value
Now we can calculate \( A \):
\[
A = 5500 \cdot 1.478 \approx 8139.6574
\]
Rounding this to the nearest cent gives:
\[
A \approx 8139.66
\]
Final Answer
The value of Arianna's investment after 7 years is \\(\boxed{8139.66}\\).