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Rolling a pair of dice. Find probability that at least one die shows a given number.

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Two fair six-sided dice are rolled.

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Let $A$ be the event that first dice shows a $\\var{number}$ $\\Rightarrow P(A)=\\frac{1}{6}$.

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Let $B$ be the event that second dice shows a $\\var{number}$ $\\Rightarrow P(B)=\\frac{1}{6}$.

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$A$ and $B$ are independent events so $P(A\\cap B) = P(A)\\times P(B)$.

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We want the probability $P(A \\cup B)$ of either $A$ or $B$ showing $\\var{number}$ and

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\\[\\begin{eqnarray*}\n \n P(A \\cup B) &=& P(A)+P(B)-P(A \\cap B)\\\\\n \n &=& P(A)+P(B)-P(A)P(B)\\\\\n \n &=&\\frac{1}{6}+ \\frac{1}{6}-\\frac{1}{36}\\\\\n \n &=& \\frac{11}{36}\n \n \\end{eqnarray*}\n \n \\]

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What is the probability of at least one die showing a $\\var{number}$?

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Probability = [[0]]

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