Hi there, I'm a bit stuck and was hoping somebody could give me a couple of pointers....(adsbygoogle = window.adsbygoogle || []).push({});

A lecturer wages that at least one pair of students in his class have birthdays on the same day. What is the minimum number of students in his class for him to be likely to win the bet?

I have assumed a Poisson formula for Pm = (n^m).(e^-n)/m!

for the probability of m pairs having their birthdays on the same day, when n is the mean number of such pairs.

I know the answer is 23 but I am really struggling to obtain this.

Any pointers would be much appreciated. Cheers

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# Poisson Formula Question

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