SOLUTION: Alice and Bill are planning to have three children. (Assume that it is equally likely for a boy or a girl to be born.) What is the probability that not all three will be of the

For 3 children, there are   = 8 possibilities of their gender combinations.


Of them, there are only two to have all three children of the same gender:  BBB  and/or  GGG
(B = Boy, G = girl).


Hence, the probability to have all three children of the same gender is   = .    


Then the probability NOT to have all three children of the same gender is the complement to it, i.e.  1 -  = .     ANSWER