1. Rewrite the equation for quintupling using \(PV\) and \(FV\):
5 = (1 + r)^{\frac{22}{3}}
2. Take the natural log on both sides:
\ln(5) = \frac{22}{3} \ln(1 + r)
3. Rearrange for \(\ln(1 + r)\):
\ln(1 + r) = \frac{3 \ln(5)}{22}
4. Exponentiate to find \(1 + r\):
1 + r = e^{\frac{3 \ln(5)}{22}}
5. Solve for \(r\):
r = e^{\frac{3 \ln(5)}{22}} - 1
6. Calculate \(r\):
r\approx0.2454\text{ or }24.54\%
Thus, the interest rate is approximately 24.54%.