(upbeat music)
- [Voiceover] The birthday paradox refers to the likelihood
of two people within a random group
sharing the same birthday.
Given the fact that there are 366 possible birthdays,
including February 29th,
- 'Sup? - [Voiceover] It doesn't
seem all that likely, but in a room of 23 people,
there's actually more than a 50 percent chance
that two of those people share the same birth date.
If that seems high, consider this,
in a group of 23 people, there are actually
253 possible chances for a match.
So, might not make sense to your brain,
but that doesn't really matter,
because, you know, math.
So we're out here on the street
to put the birthday paradox to the test.
By the time we hit 23 people there's a 50.7 percent chance
that two of them will have the same birthday.
Are we gonna be that lucky? I don't know.
Let's find out.
All right, so here's our first person,
your name is? - Bob.
- Bob, when's your birthday?
- January 30th, 1959.
- Now since you're the first person, there's no chance
of you winning this.
- [Bob] That's okay.
- When's your birthday, Casey?
- November 30th.
- [Computer] No match.
- November 26th.
- [Computer] Ooo, no match.
- October 15th.
- [Computer] That's not a match.
- Still don't have a match, but it's pretty good.
We're getting there.
Hello there sir, what's your name?
- Odin. - [Computer] Cool name.
- Odin, when's your birthday?
- June 21st. - [Computer] No way.
- September 26th. - [Computer] Not a match.
- April 15th. - [Computer] I don't think so.
- January 11th. - [Computer] Not a match.
- Here we go. - [Lady] August 25th.
- [Computer] No match.
- [Voiceover] January 23rd. - [Computer] No match.
- September 18th. - [Computer] No match.
- Rod, when is your birthday?
- My birthday is January 4th.
- [Computer] Ooo, no match.
- I'm so sorry Rod.
- Well then I guess this is goodbye.
- It is. Oh, oh!
- September 24th. - [2nd guy] October 31st.
- May 8th. - [Computer] Uh uh, nope, ooo!
- None of these are matches.
- Oh, shame. - [Host] Sorry guys.
- All right. - [Host] I'm here with?
- Jackie. - [Guy] and Fernando.
- And what do we got for birthdays?
October 31st.
- I think October 31st is a big winner.
- [Lady] Yay! - It think it's a winner.
Let's double check, Jackie--
- [Computer] That's a birthday match.
- [Host] It's a winner!
Spooky Halloween Bonus! (eerie sound effects)
- I got a special treat for you guys.
- This is the best day ever. (laughing)
- So there you go, there's your nice Halloween cake.
- [Lady] Thank you. - Guys, thank you for,
thank you for being born.
So there you have it.
16 people and we found two wonderful souls
with the same birthday, on Halloween of all days.
How spooky.
So the birthday paradox, it's a real thing.