Math Is Fun Forum

qantasqf1

Member

Registered: 2015-07-22

Posts: 1

Probability of shared birthdays

OK - I can understand how to calculate the probability of 2 people in a group of 23 sharing the same birthday, but how do I calculate the probability of 3 people in a group of 23 sharing the same birthday? Or, for that matter, 4?
Cheers,
Steve

Last edited by qantasqf1 (2015-07-22 21:57:07)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Probability of shared birthdays

All having the same birthday or some other arrangement?

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Mark 42

Member

Registered: 2015-07-24

Posts: 4

Re: Probability of shared birthdays

http://math.stackexchange.com/questions/485462/birthday-problem-for-3-people

This might help. Its a similar question.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Probability of shared birthdays

Hi;

I know the link, I am a member there. Still would like the OP to clarify a point or two.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.