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When , required probability
Key GC with either sequence or use table functions.
We want to solve
Plot and check for the x that gives a corresponding value that is less than
When , probability that all 21 people have different birthdays
Probability that all 21 people have different birthdays
Thus, when , probability that at least two of the people are the same birthday (more than )
A very interesting probability question here. This show show counter intuitive probability is! The results shows that the we can expect to find someone with the same birthday in a room of 23, more than half the time.