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The mean and the variance 10 observations are given to be 4 and 2 respectively. If every observation is multiplied by 2 , the mean and the variance of the new series will be respectively

Options

  1. A8 and 20
  2. B8 and 4
  3. C8 and 8
  4. D80 and 40

Correct answer

C. 8 and 8

Step-by-step solution

Mean ( X )=4 Variance ( X )=2 Number of observations =10 New average = (4 10) 2 10 =8 New variance =(2)^2 Variance (X)=4 2=8 Option (C) is correct.

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