Not sure if I am in the right section here. But back when I studied probability at college, I remember a standard question was what was the probability of the number of people having the same birthday in, say, an audience of 100. But cant remember at all how to calculate, but remember being surprised at the answer. Lightweight question for Science I'm afraid.
In an audience of 100 people there is a 99.9999692751% chance of any two of them sharing a birthday (just the date, not the year). In fact the probability becomes greater than 99% once the audience reaches 57 in number. Beyond that the probability raises fractionally but insignificantly until it reaches 100% at 365 (my calculations do not account for Feb....