SOLUTION: If two dies are rolled one time, find the probability of getting these results 1. A sum less than 9 2. A sum greater than 9

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Question 1153379: If two dies are rolled one time, find the probability of getting these results
1. A sum less than 9
2. A sum greater than 9

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Here are all 36 possible dice rolls:

(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)

If two dice are rolled one time, find the probability of getting these results
1. A sum less than 9

I will color red all the dice rolls with sum less than 9:

(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 26.

So the probability is 26 out of 36, or 26/36, which reduces to 13/18.

2. A sum greater than 9
I will color red all the dice rolls with sum greater than 9:

(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 6.

So the probability is 6 out of 36, or 6/36, which reduces to 1/6.

Edwin