\section{Introduction}

\generic{Setup:}
Suppose we toss a 6-sided die $n$ times. \par
It is easy to detect the first time we roll a 6. \par
What should we do if we want to annouce the \textit{last}?

\problem{}<lastl>
Given $l \leq n$, what is the probability that the last $l$
tosses of this die contain exactly one six?

\vfill

\problem{}
For what value of $l$ is the probability in \ref{lastl} maximal?

\vfill

\problem{}
Finish your solution: \par
In $n$ rolls of a six-sided die, when should we announce the last time we roll a 6? \par
What is the probability of our guess being right?

\vfill
\pagebreak