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You are going to roll two dice. Let the variable x = the sum of the numbers rolled. What is the probability that x = 9 ?

User Stbrody
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1 Answer

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The first cube can land in any one of 6 ways.
The second cube can land in any one of 6 ways.
Total number of ways that 2 dice can land = (6 x 6) = 36 ways.

For any of these ways, the sum of the numbers rolled is 9 :

3, 6
4, 5
5, 4
6, 3

There are 4 ways to roll a 9, out of a total of 36 ways that
the dice can land. So the probability of rolling a 9 is

4 / 36 = 1 / 9 = 11-1/9 percent


User Cayla
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