From your previous experience with the Poisson, Exponential, and Gamma distributions, you should also remember that each required a known value for \(\mu\) before proceeding with calculations. It is sensible to consider estimating the unknown population mean \(\mu\) using the sample mean
\begin{equation*}
\mu \approx \overline{x} = \frac{\sum x_k}{n}
\end{equation*}
where the values \(x_k\) are the n individual sample values.