if we assume, this is simple interest at 6%, since you never specified above
then we can say that [tex]\bf \qquad \textit{Simple Interest Earned}\\\\
I = Prt\qquad
\begin{cases}
I=\textit{interest earned}\to &49.27\\
P=\textit{original amount deposited}\\
r=rate\to 6\%\to \frac{6}{100}\to &0.06\\
t=years\to &\frac{325}{365}
\end{cases}[/tex]
notice, "t" is in years, so 325 needs to be converted to years by dividing it by 365
solve for "P", or the Principal amount
