SOLUTION: A pair of dice is tossed. Find the probability of scoring '7' points?

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Question 1087950: A pair of dice is tossed. Find the probability of scoring '7' points?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!

Here are all possible 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)

(1)  Count them.  How many are there? ____

Now I will color the ones red for which the sum
of the two numbers is 7:

(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)

(2)  Count the red ones.  How many are there?  ___

Make a fraction with the answer to (2) as the numerator
and the answer to (1) as the denominator.

Then reduce that fraction to lowest terms.

That fraction is the probability that you're looking for.

Edwin