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What is the standard deviation of 7,9,11,13,15 ?

Options

  1. A2.4
  2. B2.5
  3. C2.7
  4. D2.8

Correct answer

D. 2.8

Step-by-step solution

S.D. = = 1 n (x- x )^2 aligned & = 1 n [16+4+4+16] = 40 5 = 8 & =2 2 =2 1.4=2.8 aligned

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