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The table below gives an incomplete frequency distribution with two missing frequencies f₁ and f₂ . The total frequency is 18 and the arithmetic mean of X is 2 . What is the standard deviation?

Options

  1. A5 2
  2. B5 3
  3. C4 3
  4. D16 9

Correct answer

C. 4 3

Step-by-step solution

Standard deviation, aligned & = f_i x₁^2- ( f_i x_i t f_i )^2 & = 104- ( 136 2 )^2 = 4 3 . aligned

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