The usual expression of the expected value of X is:(adsbygoogle = window.adsbygoogle || []).push({});

E[X] = (sum) x*p(x)

i'm supposed to show that, for X a random non-negative discrete random(stochastic) variable, we have that:

E[X]=(sum: i from 1 to infinity) P(X>=i)

i have absolutely no idea how to do this. does anyone want to push me in the right direction?

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# Proof of expected value expression

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