Quote:
Originally Posted by Tuna
more productive than that 'MB was so much better back in the day' delusion youve been under
answer is 33% cause there's four different possibilities:
BG
GB
BB
GG
Because one of them is already a girl, that dismisses the possibility of BB, leaving:
BG
GB
GG
Since one of them is already a girl, 1/3 chance the other will also be a girl (GG)
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That isn't right...but then I though about it and it also made sense, but my answer wasn't wrong (!)
So I got frustrated, looked it up, and it's how the question is interpreted. There's a long article covering the different analysis..
Boy or Girl paradox - Wikipedia, the free encyclopedia (note in the article they switch the boy/girl)
Quote:
From all families with two children, at least one of whom is a boy, a family is chosen at random. This would yield the answer of 1/3.
From all families with two children, one child is selected at random, and the sex of that child is specified. This would yield an answer of 1/2.[3][4]
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Interpretation1: out of all families with two children with at least one girl, what are the chances of selecting one with two girls? 1/3
or
Interpretation 2: A family with 2 children is selected, one is found to be a girl, what are there being two girls? 1/2