The variance of the ungrouped data $2, 12, 3, 11, 5, 10, 6, 7$ is

Let one angle of a triangle be $60^{\circ}$. If the variance of the three angles of the triangle is $4614^{\circ}$,then the other two angles are

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:

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

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

In an experiment with $15$ observations,the results were available as $\sum X^2 = 2830$ and $\sum X = 170$. One observation that was $20$ was found to be wrong and was replaced by the correct value $30$. The corrected variance is:

If the mean of the discrete distribution $8, 9, 6, 5, x, 4, 6, 5$ is $6$,then its standard deviation (nearest to two decimal places) is