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COMPUTER SCIENCE 20, SPRING 2012 \\
DISCRETE MATHEMATICS FOR COMPUTER SCIENCE\\
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Class \#24 (Basic Probability)
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\paragraph{Homework, due in hard copy Monday 4/9/2012 at 10:10am}
\paragraph{Please write your TF's name on your homework, and list the names of any students with whom you collaborated.}
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\item You have two identical 10-sided dice numbered 1,2,...,10, with the strange property that the probability of rolling $n$ is \emph{proportional} to $n$.
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\item What is the probability of rolling an $n$? (Express your answer as some formula involving $n$.)
\item You roll these two dice at the same time. What is the probability that the sum of the two rolls is at least 18? (You can leave your answer as a fraction.)
\item Is the probability of rolling at least one 9 independent of the probability that the sum of the two rolls is at least 18? Justify your answer.
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