Question

a)write the probability of getting each number top face when a die was rolled in the following table b) find the sum of the probablities of all out comes.
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Answer 1

Out of six possibilities only once the number 4 occurs hence probability is  

6

1

​  

. Similarly we fill the remaining

Outcome 1 2 3 4 5 6

Probability (P)    1/6  

(b) The sum of all probabilities

P(1)+P(2)+P(3)+P(4)+P(5)+P(6)

=  

6

1

​  

+  

6

1

​  

+  

6

1

​  

+  

6

1

​  

+  

6

1

​  

+  

6

1

​  

=1

The sum of the probabilities of all outcomes must equal 1 . If two events have no outcomes in common, the probability that one or the other occurs is the sum of their individual probabilities. The probability that an event does not occur is 1 minus the probability that the event does occur.