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Topic: Re: The probability of boys
Replies: 19   Last Post: Dec 24, 1997 6:29 PM

 Messages: [ Previous | Next ]
 Jim Balter Posts: 181 Registered: 12/7/04
Re: The probability of boys
Posted: Dec 17, 1997 2:53 AM

No SPAM wrote:
>
> Dennis Rakestraw <drakestraw@hotmail.com> wrote in article
> <882203102.2049048581@dejanews.com>...
> [stuff deleted]
>

> > If a man says, "of my two children at least one is a boy," what is the
> > probability that both are boys? The answer, oddly, is not "50-50."

> [more stuff deleted]
>
> A finer example of sexism in mathematics will ne'er be found.
>
> If men who have one boy and one girl are as likely to start,
> "of my two children at least one is a girl" as they are to start,
> "of my two children at least one is a boy", then the answer is
> indeed 50-50.

Bzzzt! Wrong. If the man (or woman) says "at least one boy",
then the chances are 1/3 that the other is a boy.
If the man (or woman) says "at least one girl",
then the chances are 1/3 that the other is a girl.
That's where the parity comes in.

If you want to avoid sexism, then just phrase the problem
differently every other time.

--
<J Q B>

Date Subject Author
12/15/97 Dennis Rakestraw
12/15/97 Jim Balter
12/16/97 No SPAM
12/16/97 David Ullrich
12/17/97 Jim Balter
12/17/97 Xcott Craver
12/16/97 William L. Bahn
12/17/97 No SPAM
12/17/97 Darrell Ryan
12/17/97 Xcott Craver
12/17/97 Darrell Ryan
12/18/97 Xcott Craver
12/18/97 Darrell Ryan
12/22/97 Koen Samyn
12/22/97 Dave Seaman
12/24/97 standebj@SLU.EDU
12/17/97 William L. Bahn
12/18/97 Rainer Thonnes
12/17/97 Jim Balter
12/19/97 QSCGZ