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Re: How do I solve this?
Old 11-30-2005, 11:28 PM   #8
Neo
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Default Re: How do I solve this?

Ignoring the possibility that someone was born on Feb29...


P = (365)(364)(363)....(365 - n + 1)/(365)^n where n = 30.

P = .29368, which is actually the probability that no two people have the same birthday, so

1 - .29368 = .70632 => .71

So in a room with 30 people, chances are more likely than not that two people will have the same birthday. May seem counterintuitive but it's true.
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Last edited by Neo : 11-30-2005 at 11:37 PM.
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