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AP EAMCET2014MathematicsStatistics

If x₁, x₂, , x_n are n observations such that _ i=1 ^n x₁^2=400 and _ i=1 ^n x₁=80 , then the least value of n is

Options

  1. A18
  2. B12
  3. C15
  4. D16

Correct answer

D. 16

Step-by-step solution

Given, _ i=1 ^n x_i^2=400 and _ i=1 ^n x_i=80 We know, (x_i )^2 n - ( x_i n )^2 0 aligned & & 400 n - ( 80 n )^2 & 0 & & 400 n & 6400 & & n & 16 & & n & =16 aligned

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