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Let x ₁, x ₂, , x _ n be n observations such that x _ i ^2=400 and x _ i =80 . Then a possible value of n among the following is

Options

  1. A15
  2. B18
  3. C9
  4. D12

Correct answer

B. 18

Step-by-step solution

aligned & x_i^2 n ( x_i n )^2 & n 16 aligned

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