Let XXX be a discrete random variable with P(X=k)=1NP(X=k) = \frac{1}{N}P(X=k)=N1 for k=1,…,Nk=1, \dots, Nk=1,…,N. What is the variance as N→∞N \to \inftyN→∞?
∞\infty∞
111
000
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