Final answer:
Serena needs to earn an annual interest rate of approximately 4% on her investment of $31,454 to accumulate $39,800 in 6 years.
Step-by-step explanation:
Serena needs to determine the rate of interest she will need to earn annually on her investment of $31,454 to grow it to $39,800 in 6 years. To find the rate, we can use the future value formula for compound interest:
FV = PV * (1 + r) ^n
Where FV is the future value of the investment ($39,800), PV is the present value of the investment ($31,454), r is the annual interest rate (expressed as a decimal), and n is the number of years the money is invested (6 years).
We rearrange the formula to solve for r:
r = (FV/PV) ^(1/n) - 1
Plugging in the numbers:
r = ($39,800 / $31,454) ^(1/6) - 1
r ≈ 0.04 or 4%
Hence, Serena needs to earn an annual interest rate of approximately 4% to reach her goal.