Use the model $A=P e^{r t} .$ The variable $A$ represents the future value of $P$ dollars invested at an interest rate $r$ compounded continuously for $t$ years.
If a couple has $\$ 80,000$ in a retirement account, how long will it take the money to grow to $\$ 1,000,000$ if it grows by $6 \%$ compounded continuously? Round to the nearest year.