Answer:
a)
G - G
G - B
B - B
B - G
b) 25% probability that both of the children are girls.
c) 23.04% probability that both of the children are girls.
Explanation:
a. Construct a sample space for the genders of the children, using B for boy and G for girl.
B for boy
G for girl
Each child can be a boy or a girl
Two children
First child - Second child
G - G
G - B
B - B
B - G
b. Find the probability that both of the children are girls.
Two children
Each has a 50% probability of being a girl
So
0.5*0.5 = 0.25
25% probability that both of the children are girls.
c. Answer part b if, in reality, for a given child, the chance of a girl is 0.48.
Two children
Each has a 48% probability of being a girl
So
0.48*0.48 = 0.2304
23.04% probability that both of the children are girls.