The mean and $S.D.$ of $1, 2, 3, 4, 5, 6$ is

  • A

    $\frac{7}{2},\,\sqrt {\frac{{35}}{{12}}} $

  • B

    $3, 3$

  • C

    $\frac{7}{2},\,\sqrt 3 $

  • D

    $3,\,\frac{{35}}{{12}}$

Similar Questions

Calculate mean, variance and standard deviation for the following distribution.

Classes $30-40$ $40-50$ $50-60$ $60-70$ $70-80$ $80-90$ $90-100$
${f_i}$ $3$ $7$ $12$ $15$ $8$ $3$ $2$

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Statement $2$ : The sum of first $n$ odd natural number is $n^2$ and the sum of square of first $n$ odd natural numbers is $\frac{{n\left( {4{n^2} + 1} \right)}}{3}$

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