[tex]\qquad \textit{Amount for Exponential Decay} \\\\ A=P(1 - r)^t\qquad \begin{cases} A=\textit{current amount}\\ P=\textit{initial amount}\dotfill &28000\\ r=rate\to 9\%\to \frac{9}{100}\dotfill &0.09\\ t=years\dotfill &5\\ \end{cases} \\\\\\ A=28000(1 - 0.09)^{5}\implies A=28000(0.91)^5\implies A\approx 17472.90[/tex]
