SOLUTION: suppose you roll two dice find the probability of not rolling a sum of 12

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Question 622724: suppose you roll two dice find the probability of not rolling a sum of 12
Answer by math-vortex(648) About Me  (Show Source):
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Hi, there--
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The event you are interested in is "not rolling a sum of twelve with two dice."
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The probability that you will not roll a sum of 12 with two dice is a fraction represented by
[the number of ways to not roll a sum of 12 with two dice] divided by [the number of ways to roll two dice]
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First you need find the number of ways to roll two dice. There are 6 possible numbers you could roll on the first die. For each of those 6 numbers, there are 6 possibilities for the number on the second die. Therefore, the total number of ways to roll two dice is 6*6=36 ways.
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There is only one way to roll a sum of 12 with two dice. You must roll a six on the first die, and roll a six on the second die.
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This means that the are 35 ways to not roll a sum of 12.
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The probability of not rolling a sum of 12 is 35/36.