$\noindent Let $X$ be the roll number the game ends on ($X$ can take on values $1,2,3,\ldots$). Let $p = \frac{1}{8}$ and $q = 1-p$. Then $\mathbb{P}\left(X = k\right) = q^{k-1}p$, $k=1,2,3,\ldots$. Let $p_{n}$ be the probability that the game ends \textbf{before} the $n$-th roll, for...