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#1 Re: Help Me ! » Probability question » 2015-12-23 20:10:01

Yes that is right...thanks!


What about this twist....

What is the probability that one person in that 29  has their birthday on the day of my wedding June 29,1986(month and day, not the year) ...when we view my wedding as ONE date in history and not repeating like a birthday or anniversary?

Not sure it makes a difference ...hmmm

#2 Help Me ! » Probability question » 2015-12-23 07:28:59

realgains
Replies: 11

I want to know what the chances are that someone in a room of 30 has the exact same birthday as ME......

The way I understand the below  calculation, which was sent to me in answer to my question,  is that the chances of ANY PAIR in a   room of 30 that share the exact birthday is 76.6%.
That is comparing ereryone in  room to everyone else.

This was and is my question.....
What I want to know is what are the chances of anyone in the room of 30 having the exact birthday as ME...one specific person in the group?  (not the chances of any PAIR in the group having the same b-day.)



There are 30 people in a room ... what is the chance THAT ANY TWO of them celebrate their birthday on the same day? Assume 365 days in a year.


The chance of not matching:

364/365 × 363/365 × 362/365 × ... × 336/365 = 0.294...


And the probability of matching is 1- 0.294... :

The probability of sharing a birthday = 1 - 0.294... = 0.706...

Or a 70.6% chance, which is likely!

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