[tex]\bf ~~~~~~ \textit{Simple Interest Earned}\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\to &\$1500\\
P=\textit{original amount deposited}\\
r=rate\to 5\%\to \frac{5}{100}\to &0.05\\
t=years\to &10
\end{cases}
\\\\\\
1500=P(0.05)(10)\implies \cfrac{1500}{(0.05)(10)}=P[/tex]