Let $r$ be the range and ${S^2} = \frac{1}{{n - 1}}\sum\limits_{i = 1}^n {{{({x_i} - \bar x)}^2}} $ be the $S.D.$ of a set of observations ${x_1},\,{x_2},\,.....{x_n}$, then

  • A

    $S \le r\sqrt {\frac{n}{{n - 1}}} $

  • B

    $S = r\sqrt {\frac{n}{{n - 1}}} $

  • C

    $S \ge r\sqrt {\frac{n}{{n - 1}}} $

  • D

    None of these

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