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Let P be the median, Q be the mean and R be the mode of observations x₁, x₂, x₃, x n . Let S= _ i=1 ^n (2 x_i-a )^2 . S takes minimum value, when a is equal to

Options

  1. AP
  2. BQ 2
  3. C2 Q
  4. DR

Correct answer

C. 2 Q

Step-by-step solution

(x_i-a )^2 is minimum for mean =a For (2 x_i-a )^2= 4 (x_i- a 2 )^2= a 2 must be mean aligned & = a 2 =Q & a=2 Q aligned

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