Suppose values taken by a variable $x$ are such that $a \le {x_i} \le b$, where ${x_i}$ denotes the value of $x$ in the $i^{th}$ case for $i = 1, 2, ...n.$ Then..

  • A

    $a \le {\rm{Var}}(x) \le b$

  • B

    ${a^2} \le {\rm{Var}}(x) \le {b^2}$

  • C

    $\frac{{{a^2}}}{4} \le {\rm{Var}}(x)$

  • D

    ${(b - a)^2} \ge {\rm{Var}}(x)$

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