Can You Solve the “Birthday Paradox”?

this may surprise you…

Not a lot of people can get their mind around this at first glance.  So what is this paradox anyway?  We have seen some cool ones like the double – slit experiment which can sort of be described as such.  There are also some other viral ones making their way around the internet.  But what about this one?  Just about everyone has been in some sort of a classroom before and everyone has a birthday 😉

Imagine sitting in a classroom. Let’s say there are 30 people in the class. What are the odds that two people in the room have the same exact birthday? Mathematician Amir Aczel poses this question to a packed auditorium and engages the front rows in what is known as the “birthday problem.” The results may surprise you.

Ok so do you have any prelim guesses on this or strategy for solving it?

Does this involve algebra or more advanced statistics?

Let’s solve this math riddle in the video on page 2

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  1. Clay Noll said:

    In average I’d say 1/15 chance since schooling is yearly or by age but there should be adjustment by month and seasonal relation by region.

    That is, average “sexy time” months following gestation periods per the comon weather patters for that area.

    What months do citizens procreate more vigorisly vs seasons or periods that they lack. Further coalesced with changing sexual norms of a increasingly and changing sexual environment per the modern “hookup culture” and further adjusted for our modern accessibility to abortion and contraceptive application.

  2. David Soltis said:

    When one reads anything about astrology, you immediately say “that’s true, that’s me”. But do you really see how ambiguous the predictions are?. “Fortune will come soon” for example. Umm ok. This can be taken as a fortunate fun weekend. A raise at work. A fortunate lesson learned in your failures. Humans are slightly more tipped on the scale to believe ambiguity without ascertaining the possibility of variability in their interpretation of what these so called predictions mean. I can read all birthday predictions. And they’re all so ambiguous. Your Own perception makes you believe these things happen, in a sort of “kind-of” sense.

  3. Kristopher Adam Byrd said:

    There were four other people in my school with the same birthday as mine. Who gives a flying$#%&!@* There’s billions of people walking the earth right now but only 365 days in a year….Why don’t you just go ahead and try to calculate how many people are taking a fat$#%&!@*at the same time you are while you’re at it, you boring bitches….

  4. Tim Johnson said:

    Actually, real astrology, as opposed to newspaper column astrology, takes into account 100s of variables. And does not explain traits every person has.

  5. Johnathan Humbers said:

    No I think it’s dumb to me. Seems like scientist as jus pulling names of weird$#%&!@*out a hat and say hey let’s call this that. And make it seem real

  6. Chris Haynes said:

    A lot of big words…..compensating for a little something else maybe? Do you even understand the definitions of half of the words you tried using? #bigwordsmakemydickbigger

  7. Dave Carvell said:

    The odds might be small as far as someone in the group having *your* birthday, but if you have as 30 people in a group, there is a great likelihood of *some pair* of two people sharing a birthday.

  8. Kevin Wagenknecht said:

    I have noticed this through out my life and I have a theory on it. This is the result of modern obstetrics. Since the 1950s it is common practice for dr.s to go ahead and incuduce women into labour so they have the baby Monday through Friday and not during a holiday. Also baby’s not born vaganal are delivered Monday through Friday and not on holidays unless it is an emergency. With most common days being wed. And Friday . This fits around the drs. And hospitals schedules. Of course you also have your monthly variance as well to consider certain months seem more prone for folks to have new babies in. That’s my observations and theory on that.

  9. Jordan Page-ii said:

    Roughly 691,666,667 birthdays per month… that’s roughly 23,055,555 birthdays per day. Doesn’t seem strange at all. High frequency.