[tex]~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill&\$1200\\ P=\textit{original amount deposited}\dotfill & \$5000\\ r=rate\to r\%\to \frac{r}{100}\\ t=years\dotfill &3 \end{cases} \\\\\\ 1200=(5000)\left( \frac{r}{100} \right)(3)\implies 1200=150r\implies \cfrac{1200}{150}=r\implies 8=r[/tex]
