## Precalculus (6th Edition) Blitzer

$14.6$ years
The formula for continuously compound interest is given by : $A= Pe^{rt}$ Plug in the given data. $150,000=(50,000) e^{0.75t}$ or, $3 =e^{0.75t}$ Take the natural log of each side. $\ln 3 =0.75 t \implies t \approx 14.6$ years