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If the mean and the sum of squares of 10 observations are 40 and 16160 respectively, then what is the standard deviation?

Options

  1. A16
  2. B6
  3. C5
  4. D4

Correct answer

D. 4

Step-by-step solution

Since, = x ^2 n - ( x n )^2 aligned & = 16160 10 -(40)^2 & = 1616-1600 = 16 =4 aligned

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