

\subsection{\bf Example of Birth/Death Process---II}

\begin{slide}
\begin{itemize}
\item It is also easy to do---the seemingly harder problem---of a finite
number of telephone lines in exchange.  

\item There is an example of this
sort in problem set about parking lots.

\item Similar techniques can be used to decide on a number of servicemen
needed to repair a set of machines of prescribed reliability.  Here,

\begin{description}
\item{$\bullet$} Death = machine starts working
\item{$\bullet$} Birth = machine breaks down, and
\item{$\bullet$} $E_n = n$ machine's broken.
\item{$\bullet$} There is a beautiful discussion of this on pages
416--420 of Feller.
\end{description}
\end{itemize}
\end{slide}

