In a class, average height of all students is '$a$ ' cms. Among them, average height of $10$ students is '$b$' cms and the average height of the remaining students is '$c$' cms. Find the number of students in the class. (Here $a>c$ and $b>c$ )

  • A

    $\frac{(a(b-c))}{(a-c)}$

  • B

    $\frac{(b-c)}{(a-c)}$

  • C

    $\frac{(b-c)}{10(a-c)}$

  • D

    $\frac{10(b-c)}{(a-c)}$

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