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The standard deviation of the numbers 22, 26,28,20,24,30 is

Options

  1. A2
  2. B2.4
  3. C3.24
  4. D3.42

Correct answer

D. 3.42

Step-by-step solution

Given numbers 22, 26, 28, 20, 24, 30 x = 22+26+28+20+24+30 6 = 150 6 =25 Now, (x_i- x )^2 is 9,1,9,25,1,25 aligned & Now, S D= (x_i- x )^2 n & = 9+1+9+25+1+25 6 = 70 6 =3.42 aligned

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