SOLUTION: If 2 dice are rolled what is the probability that the score on the dice is 9 or they both show the same number?

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Question 335057: If 2 dice are rolled what is the probability that the score on the dice is 9 or they both show the same number?
Found 2 solutions by stanbon, Edwin McCravy:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If 2 dice are rolled what is the probability that the score on the dice is 9 or they both show the same number?
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# of ways to get a sum of 9: 3/6 ; 4/5 ; 5/4 ; 6/3::::4 ways
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# of ways to show the same number: 6
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The events are mutually exclusive so,
P(sum of 9 or pair) = (4+6)/36 = 10/36 = 5/18
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Cheers,
Stan H.

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!

Here is the sample space. It contains 36 possible outcomes:

(1,1)  (1,2)   (1,3)  (1,4)   (1,5)  (1,6)

(2,1)  (2,2)   (2,3)  (2,4)   (2,5)  (2,6)

(3,1)  (3,2)   (3,3)  (3,4)   (3,5)  (3,6)

(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)

(5,1)  (5,2)   (5,3)  (5,4)   (5,5)  (5,6)

(6,1)  (6,2)   (6,3)  (6,4)   (6,5)  (6,6)

Now I will color the ones red for which either the score is 9 
or they both show the same number?


(1,1)  (1,2)   (1,3)  (1,4)   (1,5)  (1,6)

(2,1)  (2,2)   (2,3)  (2,4)   (2,5)  (2,6)

(3,1)  (3,2)   (3,3)  (3,4)   (3,5)  (3,6)

(4,1)  (4,2)   (4,3)  (4,4)   (4,5)  (4,6)

(5,1)  (5,2)   (5,3)  (5,4)   (5,5)  (5,6)

(6,1)  (6,2)   (6,3)  (6,4)   (6,5)  (6,6)


    
Count the red ones.  There are 10 of them, the probability that
the score on the dice is 9 or they both show the same number is
10%2F36 which reduces to 5%2F18.

Edwin