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# Birthday paradox - Try this out Watch

1. Hey there =]

Don't know if you've heard of the birthday paradox, but it basically states that once you reach 57 people in a room there is a 99% chance that they share the same birthday.

So to try this out, just post your birthday and we'll see how many people it takes before a birthday is shared

To start off - June 18th
2. Sounds fun! 5th of June.
3. June 25th
4. January 8th

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5. 17th September
6. 23rd of July

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7. 5th of September
8. 3rd march
9. 9th September

In the do you share your birthday with a famous person thread, within 2 pages there were 2 other people with my birthday (and exact birthdate!) and at least 2 other pairs of shared birthdays.

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10. (Original post by 1992LP)
Sounds fun! 5th of June.
so close! 6th of june
11. 23rd january

Anyone?
12. 28th of June, anyone?
13. 21st November
14. 31st of dec
15. 30th August
16. 26th February
17. 8th April

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18. 7th July

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19. 30th november
20. (Original post by Andy_J)
I have no idea how that works since the odds are 1 in 365 but ill go with it.

30th May
To get a 100% chance of success, you need 367 people due the the 1 in 366 (leap year) probability. However when the probability is under 100%, combinations increase the probability a lot quicker.

2 people, only 1 way in which the birthday can be shared
3 people there are 3 ways
4 people there are 6 ways
5 people there are 10 ways
etc...

and at 57 people, there are 1596 possible combinations!

Hence the high chance at such a low number!

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Updated: June 9, 2017
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