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CBSE Class 12-science Answered

Define variance and standard deviation of a random variable.
Asked by Topperlearning User | 04 Jun, 2014, 01:23: PM
Expert Answer

Variance of a Random Variable: Let X be a random variable whose possible values x1, x2, x3, ..., xn occur with probabilities p1, p2, p3,..., pn, respectively. Also,be the mean of X. The variance of X, denoted by Var (X) is defined as                                       

 
Standard Deviation of a Random Variable: The non-negative number;
 is called the standard deviation of random variable X.
Answered by | 04 Jun, 2014, 03:23: PM

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