so i'm somewhat new to statistics proofs, but this one is for the most part a sets proof, which i can do. i'm having trouble connecting them.(adsbygoogle = window.adsbygoogle || []).push({});

(c = complement)(AB = A intersect B)

Let A_1, A_2... be any infinite sequence of events, and let B_1, B_2... be another infinite sequence defined as B_1=A_1, B_2=A_1cA_2, B_3=A_1cA_2cA_3 and so on.

Prove that Pr(Union i=1 to n A_i) = Sum i=1 to n Pr(B_i).

(sorry if that notation is hard to understand)

So i've convinced myself that this is true. I see if i take the union of A_i up to n, that B_i up to n is equal. Each B_i is A_i minus any previous As that intersect it. I'm just having trouble saying that in math. If I had to write a proof right now, I'd say each Sum B_i = Union A_i, so they're equal.

So yeah, if i could get some hints on where to start. Thanks.

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# Looking for a hint on a stats proof

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