Yes, the answer to question one is definitely wrong. The author was arguing that the chances (or probability) of it being a girl is 2/3. However, that statement is wrong. It was based on the assumption that:
BG 1/3
GB 1/3
BB 1/3
However, if we are to work it out that way, it should be:
B1 G1 1/4
G1 B1 1/4
B1 B2 1/4
B2 B1 1/4www.ddhw.com
As stated by a previous poster, the BB combination should be counted twice. As such, it will end up that there is a 50/50 chance of it being a Girl or Boy. www.ddhw.com
So teh conclusion is: The guy should have his pay deducted by 10000USD per month!!!!