The mean of marks secured by $50$ students in division $A$ of class $X$ is $61,\,25$ students of division $B$ is $57$ and that of $50$ students of division $C$ is $55 .$ What will be the mean of marks of the students of three divisions of Class $X$ ?

  • A

    $57.1$

  • B

    $56.4$

  • C

    $59.2$

  • D

    $57.8$

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