Statistics: when is N large?

• Jun 10th 2008, 02:55 PM
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Statistics: when is N large?
Hello! I'm having a little difficulty trying to discern when $n$ is considered large. I keep coming across formulae that end with a reference to $n large$ (attached). How do I know when N is large, and how does that change the way I solve the question?

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• Jun 10th 2008, 03:02 PM
Nyoxis
I'm used to different notation, but I think n should be 30 or more.