Suppose a class has $7$ students. The average marks of these students in the mathematics examination is $62$, and their variance is $20$ . A student fails in the examination if $he/she$ gets less than $50$ marks, then in worst case, the number of students can fail is

  • [JEE MAIN 2022]
  • A

    $5$

  • B

    $3$

  • C

    $4$

  • D

    $0$

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