Let X be a discrete random variable assuming values x1, x2, ..., xn with probabilities p1, p2, ..., pn, respectively. Then variance of X is given by(A) E (X2) (B) E (X2) + E (X) (C) E (X2) – [E (X)]2(D) √(E(X2 ) – [E (X)]2)

Let X be a discrete random variable assuming values x1, x2, ..., xn wi

1.	Let X be a discrete random variable assuming values x1, x2, ..., xn with probabilities p1, p2, ..., pn, respectively. Then variance of X is given by(A) E (X2) (B) E (X2) + E (X) (C) E (X2) – [E (X)]2(D) √(E(X2 ) – [E (X)]2)
Answer» The correct answer is (C).

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Let X be a discrete random variable assuming values x1, x2, ..., xn with probabilities p1, p2, ..., pn, respectively. Then variance of X is given by(A) E (X2) (B) E (X2) + E (X) (C) E (X2) – [E (X)]2(D) √(E(X2 ) – [E (X)]2)

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