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Question
Mark the correct alternative in the following question:
Let X be a discrete random variable. Then the variance of X is
Options
E(X2)
E(X2) + (E(X))2
E(X2) - (E(X))2
\[\sqrt{E\left( X^2 \right) - \left( E\left( X \right) \right)^2}\]
Solution
Since, the variance of a discrete random variable X is given by:
Var(X) = E(X2) - (E(X))2
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