Let $\mu$ be the mean and $\sigma$ be the standard deviation of the distribution:
$X_i$$0$$1$$2$$3$$4$$5$
$f_i$$k+2$$2k$$k^2-1$$k^2-1$$k^2-1$$k-3$
where $\sum f_i=62$. If $[x]$ denotes the greatest integer $\leq x$,then $[\mu^2+\sigma^2]$ is equal to:

  • A
    $8$
  • B
    $7$
  • C
    $6$
  • D
    $9$

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