Question

You and your spouse decide that you want to have three children: two boys and a girl. What are your chances of achieving this if:
(1) you don't care in what order the children appear?
(2) if you want to have boy, boy, girl?

Answer 1

so, if you don't care its .5 * .5 *.5
If you do care, I think what you need to do is set it up as a Pr (A|B) question;
where Pr (A|B) = Pr(A intersecting B)/Pr (B)
where Pr (B) = Pr (2 boys and a girl), and A = BBG.