Isn’t the answer supposed to be (12x11x10x9x8)/(12^5) ?

Why is Greg considering the number of pairs possible amongst 5 people and then raising the probability of 2 people not sharing a birth month to that power?

Isn’t the answer supposed to be (12x11x10x9x8)/(12^5) ?

Why is Greg considering the number of pairs possible amongst 5 people and then raising the probability of 2 people not sharing a birth month to that power?

Your answer seems to be right, but I want to take a look at the context of this question as well.

Can you please mention the Week and the Day of this video.

The General Formula is :

P(\textsf{there are shared birthdays among "n" people}) = 1 - \dfrac{365!}{(365- n)! \times365^{(n)}}

P.S. I remember that Greg may have gave some explanation on whether this calculation in the video was correct or not in some class in the past but I can’t remember the class name at the moment

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Hi, yes me too.

I was thinking maybe the question for the solution wasn’t framed right?

Probably the question would be “What is the probability that no two pairs of individuals share a birth month?”

I’m not sure though.

Regarding the video:

It is under Gre Quant Concepts which is included in the 2-month preparation plan titled “Probability Practice”.

Hi, yes

That is for correct not sharing a birth date.

Same logic as the above question… but not sure what the question for the above solution is.