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# Independence equation S1 probability watch

1. Can somebody explain to me the independence equation in S1
It is p(AnB)=P(A)XP(B) but I dont understand why this occurs and why this is only for independent events?
2. (Original post by JakeRStudent)
Can somebody explain to me the independence equation in S1
It is p(AnB)=P(A)XP(B) but I dont understand why this occurs and why this is only for independent events?

this explains it very well i think
3. (Original post by JakeRStudent)
Can somebody explain to me the independence equation in S1
It is p(AnB)=P(A)XP(B) but I dont understand why this occurs and why this is only for independent events?
When the events are independent then the fact that A happens will have no effect on whether or not B happens. So P(B|A) = P(B). so P(AnB) = P(A) P(B|A) = P(A) P(B).

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