Submit your own Neatorama post and vote for others' posts to earn NeatoPoints that you can redeem for T-shirts, hoodies and more over at the NeatoShop!

Trivia: The Birthday Paradox

In a room of 57 or more people, the probability of two people having the same birthday is 99%.

In a group of 23 randomly chosen people, that probability is 50%. For a full explanation, see Birthday Paradox [wiki]

Sad that this should become known as a paradox, as there is nothing paradoxical about it. It may be difficult to believe, but it does not contradict itself.
Abusive comment hidden. (Show it anyway.)
So with todays public education, math is now a strange and wonderful bit of magic to impress simpletons at gatherings.

How long until someone who can do simple math without a calculator is burned at the stake for witchcraft?
Abusive comment hidden. (Show it anyway.)
How is that a paradox or even surprising? The exact number needed to hit 99% might need a little math to figure out, but the fact it is around 57 should be no surprise to any high school graduate.

Your government schools at work.
Abusive comment hidden. (Show it anyway.)
I takes a little while to get use to the idea... I am curious how to solve the Birthday Paradox without using this inversion approach.

Say there are 4 students in the class, what is the probability that 2 or more student has the same birthday? I would like to know how to so solve this WITHOUT using the inversion technique[1 - {364/365 * 363/365 * 362/365}]. I believe it involve some
Abusive comment hidden. (Show it anyway.)
Login to comment.
Click here to access all of this post's 4 comments

Email This Post to a Friend
"Trivia: The Birthday Paradox"

Separate multiple emails with a comma. Limit 5.


Success! Your email has been sent!

close window

This website uses cookies.

This website uses cookies to improve user experience. By using this website you consent to all cookies in accordance with our Privacy Policy.

I agree
Learn More