\documentclass[12pt,HW250,ifthen]{article} \usepackage{comment} \newcommand{\into}{{\rightarrow}} \newcommand{\lf}{\left\lfloor} \newcommand{\rf}{\right\rfloor} \newcommand{\lc}{\left\lceil} \newcommand{\rc}{\right\rceil} \newcommand{\Ceil}[1]{\left\lceil {#1}\right\rceil} \newcommand{\ceil}[1]{\left\lceil {#1}\right\rceil} \newcommand{\floor}[1]{\left\lfloor{#1}\right\rfloor} \newcommand{\Z}{{\sf Z}} \newcommand{\N}{{\sf N}} \newcommand{\Q}{{\sf Q}} \newcommand{\R}{{\sf R}} \newcommand{\Rpos}{{\sf R}^+} \usepackage{amsmath} \begin{document} \centerline{Homework 9, Morally due Tue Apr 23, 3:30PM} \centerline{\bf THIS HW IS TWO PAGES!!!!!!!!!!} \newif{\ifshowsoln} \showsolntrue % comment out to NOT show solution inside \ifshowsoln and \fi blocks. \begin{enumerate} \item (40 points) Throughout this problem Bill has a 2-sided dice with numbers 1,2 and a 3-sided die with numbers 1,2,3. \begin{enumerate} \item (15 points) Assume both dice are fair. Bill throws both of them. For $2\le i\le 5$ give the prob that the sum is $i$. \item (20 points) Let $0\le p\le \frac{1}{2}$. Assume the 2-sided dice is fair but the 3-sided dice has Prob of 1 = $p$ Prob of 2 = $1-2p$ Prob of 3 = $p$ Bill throws both of them. For $2\le i\le 5$ give the prob that the sum is $i$. \item (5 points) Let $p$ be as in the last part. Is there a value of $p$ such that all of the sums $2,3,4,5$ come up with the same probability. \item (0 points but thing about it) Can you load two 6-sided dice to get fair sums? \end{enumerate} \centerline{\bf GO TO NEXT PAGE} \newpage \item (60 points) On the planet Vorlon they play a game that is similar to what we call Poker but with a different deck of cards. Every card has a rank from $\{1,2,\ldots,7\}$. Every card has a suite from $\{R,B\}$. Every player gets 3 cards. In most of the questions we will ask for the prob of a certain type of hand. Give the answer to 4 places since the last question is to rank them. \begin{enumerate} \item What is prob of a straight that is NOT a flush (e.g., $3R$, $4R$, $6B$) We DO allow wrap-around, so 7-1-2 counts. \item What is prob of a flush that is NOT a straight (e.g., $2R$, $4R$, $9R$) \item What is prob of a straight flush (e.g., $3R$, $4R$, $6R$) We DO allow wrap-around, so 7-1-2 counts. \item What is prob of a pair (e.g., $3R$, $4B$, $7R$). Note that a pair cannot be a straight of a flush. \item What is prob of getting NOTHING- a hand that is neither a straight, nor a flush, nor does it contain 2 of a kind. (e.g., $3R$, $5R$, $6B$) \item Rank the types of hands from most likely to least likely. \end{enumerate} \end{enumerate} \end{document}