A family plans to have three children. The husband and wife are trying to determine the probabilities of the different gender outcomes for the children.
The husband thinks that the probability that the couple will have exactly two boys is greater than the probability that the couple will have exactly one girl. The wife disagrees. She thinks that the two probabilities are equal. The sample space of outcomes is listed below. B represents a boy, and G represents a girl. Who is correct, the husband or the wife?

BBB BGB GGB GBG
BBG GBB BGG GGG