The Birthday Paradox

[FatCat]

Ina room of 23 random peoplethe probability of two of them sharing a birthday is 50 percent. Increase the number of people to just 70 and the probability is 99.9 per cent.

The probability reaches 100% when the number of people reaches 366.

 

[ThePrisoner]

Paradox? It's school boy statistics.

 

[FatCat]

Paradox? It's school boy statistics.

I didn’t make it that’s just what it’s called.
I guess the paradox is you would expect it to be more linear and not to hit the 99 per cent with such a small number of people as 70.

Birthday problem - Wikipedia

en.m.wikipedia.org

 

[ThePrisoner]

You'll have to find a school boy to explain it to me