Thread: Birthday Paradox

Apparently, there are two methods of solving this probability problem. The first, using p(n) = 1 - (365^n falling / 365^n) makes sense to me; however, there is an alternate solution using the Taylor series of e^x.

Here's the full solution on Wikipedia:
Birthday problem - Wikipedia, the free encyclopedia

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Originally Posted by jrkevinfang1234

Apparently, there are two methods of solving this probability problem. The first, using p(n) = 1 - (365^n falling / 365^n) makes sense to me; however, there is an alternate solution using the Taylor series of e^x.

Here's the full solution on Wikipedia:
Birthday problem - Wikipedia, the free encyclopedia

I got lost at the transition from


to



What's happening here?

and so

I have an interesting situation. My friend and I have the same birthday. One of her siblings and one of my siblings have the same birthday. She has 2 sibs and I have 6. What are the odds and probability of that occuring? Thanks for responding.