The problem doesn't state the sequence, so there's no reason to assume it.
Joel Send a noteboard - 25/05/2010 08:56:09 AM
Which one is born first. And Monty Hall works. I have tried it experimentally.
Hence, as in Birdeyes first example, saying boy/girl is different from girl/boy is like saying "no, I didn't roll a four and a three, I rolled a three and a four. "
Again, the only way you don't end up with the same 50/50 shot he did (and the way I initially looked at it was that by stating one child is a boy you've made it a determined event, so you're down to ONE childs possible genders: 50/50) is if we take "One is a boy born on a Tuesday" to mean "they are not BOTH boys born on a Tuesday, only one of them is. " Again, in that case there's slightly less than a fifty percent chance the other one is a boy, since a child of either gender can be born on any day of the week (making 7 days for 2 genders, a total of 14) EXCEPT Tuesday, because one and only one boy was already born on Tuesday. Six days on which a boy can be born plus seven days on which a girl can be make a total of thirteen outcomes, of which six are boys: 6/13.
However, even that assumes something not explicitly stated in the problem; it could be "one of them is a boy born on Tuesday, and so is the other one" and we're back to 50/50.
The problem here is not so much one of math as of language, though it does illustrate why so many people hate word problems. It seems that the world has two people: One is a person with good verbal skills and little mathematical acuity; what is the probability the other is someone with good math skills but few lingual ones?
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Last First in wotmania Chat
Slightly better than chocolate.
Love still can't be coerced.
Please Don't Eat the Newbies!
LoL. Be well, RAFOlk.
Recreational mathematics
24/05/2010 09:17:27 PM
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How is boy/girl different from girl/boy?
25/05/2010 01:05:15 AM
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I think it has to do with sequence
25/05/2010 08:37:05 AM
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The problem doesn't state the sequence, so there's no reason to assume it.
25/05/2010 08:56:09 AM
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Faulty "logic". 2/4
25/05/2010 02:12:54 AM
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I was going to say.
25/05/2010 02:48:38 AM
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Yeah
25/05/2010 05:05:16 AM
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Re: Yeah
25/05/2010 09:52:58 AM
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I don't know Python, but I think I know what went wrong there.
25/05/2010 11:33:18 AM
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Re: I don't know Python, but I think I know what went wrong there.
25/05/2010 01:53:01 PM
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Ah, I see now; sorry.
25/05/2010 02:27:05 PM
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You realize this thread now contains the words "Monty" and "Python" several times, right?
26/05/2010 11:01:24 AM
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