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Birthday paradox - Try this out Watch

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    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
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    Sounds fun! 5th of June.
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    June 25th
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    January 8th


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    17th September
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    23rd of July

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    5th of September
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    3rd march
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    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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    (Original post by 1992LP)
    Sounds fun! 5th of June.
    so close! 6th of june
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    23rd january

    Anyone?
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    PS Reviewer
    28th of June, anyone?
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    21st November
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    31st of dec
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    30th August
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    26th February
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    8th April


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    7th July


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    30th november
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    (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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