I have a challenge to find the following:
How many people do you need, to have a 50% or better chance of finding two persons with the same birthday (month/day)?

How many people do you need, to have 50% or better chance of finding two persons with the same birthdat (month/day)?

the probability that 2 people in a group of n people will have the same birthday is

p(n)=1-{ 365! \over 365^n (365-n)!}

This is 50.7% for n = 23.

I don't understand the value of n in the equation so that I can compute it

I told you what n is in my answer. Please read it again.

The rate button is for indicating an answer as correct or incorrect. My answer was not incorrect. Did you think that replying in the thread and EMAILING ME was not enough?

The 'n' in Capuchin's formula is the number of people in the group in question.