Assume that all elementary events in teh same samplace space

Assume that all elementary events in teh same samplace space are equally likely.

A pair of fair dice are tossed. What is the probability of obtaining a sum of 6? 5? 12?

probability of obtaining a sum of 6?

probability of obtaining a sum of 5?

probability of obtaining a sum of 12?

Solution

A: sum =6

B: sum =5

C: sum =12

n(A) = 5 ((1,5)(2,4)(3,3)(4,2)(5,1))

n(B)=4 ((2,3),(3,2),(1,4),(4,1))

n(C)=1 (6,6)

total number = 6*6 = 36

P(A) = n(A)/ total number of events = 5/36

P(B) = n(B)/total number of events = 4/36

P(C) = n(C)/total number of events = 1/36