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Let x i 1 ≤ i ≤ 10 be ten observation of a random variable X . If ∑ i = 1 10 x i - p = 3 and ∑ i = 1 10 x i - p 2 = 9 where 0 ≠ p ∈ R , then the standard deviation of these observations is:

Options

  1. A4 5
  2. B3 5
  3. C9 10
  4. D7 10

Correct answer

C. 9 10

Step-by-step solution

Standard Deviation S . D . = ∑ i = 1 10 x i - p 2 10 - ∑ i = 1 10 x i - p 10 2 = 9 10 - 3 10 2 = 9 10

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