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MHT CET20249 May 2024Evening ShiftMathematicsStatisticsActual

The variance of 20 observations is 5. If each observation is multiplied by 3 and then 8 is added to each number, then variance of resulting observations is

Options

  1. A35
  2. B55
  3. C25
  4. D45

Correct answer

D. 45

Step-by-step solution

- Variance Calculation: - Given: Variance =5 for 20 observations. - Each observation is multiplied by 3: Variance gets multiplied by 3^2= - New variance: New variance =9 5=45 - Adding 8 to each observation does not change the variance. - Final variance: 45. Answer: 45, which matches the solution shown.

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