SOLUTION: An unbiased die is thrown two times. Write down the sample space. Also find the probability that (i) first die shows 5 or sum of the upper faces is more than or equal to 8, (ii) se

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Question 1166035: An unbiased die is thrown two times. Write down the sample space. Also find the probability that (i) first die shows 5 or sum of the upper faces is more than or equal to 8, (ii) second die shows 4 or sum of the upper faces is more than 10.
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Write down the sample space.
Here's the sample space:

(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)

(i) first die shows 5 or sum of the upper faces is more than or equal to 8,

Count the red ones, that's the numerator of the answer.
Count all of them, red or black, that's the denominator of the answer

(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)

(ii) second die shows 4 or sum of the upper faces is more than 10.
Count the red ones, that's the numerator.
Count all of them, red or black, that's the denominator.
Reduce the fraction. That's the answer.


(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)

Edwin