Suppose that p = P(female birth) = 0.5. A couple wishes to have exactly one female child in their family. They will have children until they have a girl, then they will stop having children.
Question 1. What is the probability that the family has three children?
Question 2. What is the probability that the family has at most three children?
Question 3. How many male children would you expect this family to have?
Question 4. How many children would you expect this family to have?