[tex]\bf ~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill &8250\\ P=\textit{original amount deposited}\dotfill \\ r=rate\to 5.5\%\to \frac{5.5}{100}\dotfill &0.055\\ t=years\dotfill &30 \end{cases} \\\\\\ 8250=P(0.055)(30)\implies \cfrac{8250}{(0.055)(30)}=P\implies 5000=P[/tex]