here is what i was thinking

n(S) = 365^25

n(nobody born on the same day) = 365P25

n(somebody born on the same day) = 365^25 - 365P25

P(somebody born on the same day) = (365^25 - 365P25)/365^25

but when I compute this the number I get is .568 which would mean that there is a 56.8% chance that two of the 25 would be born on the same day.

This seems a little high to me, but I guess it could be right...

I was hoping somebody could shed a little light for me, or confirm my results