[tex]\bf ~~~~~~ \textit{Simple Interest Earned}
\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\to &\$144\\
P=\textit{original amount deposited}\\
r=rate\to 4\%\to \frac{4}{100}\to &0.04\\
t=years\to &1
\end{cases}
\\\\\\
144=P(0.04)(1)\implies \cfrac{144}{(0.04)(1)}=P\implies 3600=P[/tex]
