This is a cute little problem - one that looks straightforward when it isn't!
boy-or-girl.txt
Mary, Bob, and Alice are playing a noisy game in the park where you are trying to read. The two girls are as boisterous as the boy ruining your hopes of a quiet afternoon. You look up with a sigh and the woman sitting next to you catches your eye.
"I do hope my children aren't disturbing you." she says.
"It's alright," you reply politely, "It must be hard to manage three kids at that age."
"Oh only two are mine!" she laughs, "Alice and ______"
What is the probability that
* she ends with "Bob" = ___%
* she ends with "Mary" = ___%
Think about it!
Try and be sure of the answer before checking out the
the solution!
UPDATE: 2009-01-15
Amit Bali pointed out that it had to be made clear the woman had no kids at home. So in case you were wondering if the woman had more kids stashed away at home - she doesn't!
Thanks Amit!
