#1
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Unusual birthday puzzle
This was posted on usenet a few years ago. Which of the following is more likely?
A) 365 random people have 365 different birthdays. B) 365^2 random people don't have all 365 birthadys. The probabilities are close. Ignore February 29th. |
#2
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Re: Unusual birthday puzzle *DELETED*
Post deleted by random
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#3
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Re: Unusual birthday puzzle
--deleted since what was once a question will now look like an unwarranted attack--
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#4
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Re: Unusual birthday puzzle
aradsfa;lsk i'm retarded, 6am, going to sleep
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#5
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Re: Unusual birthday puzzle
[ QUOTE ]
This was posted on usenet a few years ago. Which of the following is more likely? A) 365 random people have 365 different birthdays. B) 365^2 random people don't have all 365 birthadys. The probabilities are close. Ignore February 29th. [/ QUOTE ] ok i am foolish enough to take a shot ( just like how i bluff the river with 8 high) P(A) == 1/(365!) P(B) >= 365*((364/365)^(365^2)) Am i close? I will guess that B is more likely |
#6
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Re: Unusual birthday puzzle
[ QUOTE ]
..will now look like an unwarranted attack [/ QUOTE ] Certainly not. I said something stupid and it needed to be pointed out. I appreciate you deleting it, though. See ya. |
#7
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Re: Unusual birthday puzzle
Well, they are close in order of magnitude. If anyone is
so inclined, they can check that the first probability is roughly bigger by a factor of sqrt(2xpix365). (For those who are mathematically inclined, it's almost immediate from Stirling's approximation). |
#8
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Re: Unusual birthday puzzle
im just curious, but how the hell did 2 pi get into a formula with 365 days?? [img]/images/graemlins/smile.gif[/img]
I should really learn this crap |
#9
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Re: Unusual birthday puzzle
[ QUOTE ]
how the hell did 2 pi get into a formula with 365 days? [/ QUOTE ] Pi has nothing to do with the day count. Call it N days and then relate the 2 functions/series/whatever. That relation is where the guy is saying that pi comes from. I don't know if he's right since I didn't investigate further, but that's what he means. I think. ~D |
#10
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Re: Unusual birthday puzzle
Not a math guy but B
My guess would be that A isn't close. |
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