SOLUTION: A pair of dice is rolled. What is the probability that the sum of the numbers rolled is either 7 or 11? Show your solution

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Question 1192690: A pair of dice is rolled. What is the probability that the sum of the numbers rolled is either 7 or 11? Show your solution
Found 2 solutions by Alan3354, greenestamps:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
1. Pair of dice is rolled. What is the probability that the sum of the numbers rolled is either 7 or 11?
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The possible sums are 2 to 12 inclusive ---> 11 possibilities.
Label the dice A and B:
For a sum of 7:
A   B
1   6
2   5
3   4
4   3
5   2
6   1

6 of 11 ---> 6/11
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For a sum of 11:
A   B
5   6
6   5

2 possibilities ---> 2/11
7 or 11 ---> 8/11
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Show why this doesn't work.



Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


The total number of possible outcomes when rolling two ordinary dice is 6*6=36.

6 of those outcomes have a sum of 7: 1+6, 2+5, 3+4, 4+3, 5+2, and 6+1.
2 of those outcomes have a sum of 11: 5+6 and 6+5.

The number of ways of getting a sum of 7 or 11 is 6+2=8; the total number of possible outcomes is 36.

ANSWER: P(7 or 11) = 8/36 = 2/9