Question

Write an exponential function to model the situation. A population of 470 animals decreases at an annual rate of 12%.

Answer 1

$\bf \qquad \textit{Amount for Exponential Decay} \\\\ A=P(1 - r)^t\qquad \begin{cases} A=\textit{accumulated amount}\\ P=\textit{initial amount}\to &470\\ r=rate\to 12\%\to \frac{12}{100}\to &0.12\\ t=\textit{elapsed time}\\ \end{cases} \\\\\\ A=470(1-0.12)^t\implies A=470(0.88)^t$