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The variance of 20 observations is 5 . If each observation is multiplied by 3 , then what is the new variance of the resulting observations?

Options

  1. A5
  2. B10
  3. C15
  4. D45

Correct answer

D. 45

Step-by-step solution

New variance =k^2 (old variance) =3^2 5=9 5=45

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