The standard deviation of the scores $505, 510, 515, 520, \ldots, 595$ is

The following values are calculated in respect of heights and weights of the students of a section of Class $XI$:

Measure	Height	Weight
Mean	$162.6 \ cm$	$52.36 \ kg$
Variance	$127.69 \ cm^2$	$23.1361 \ kg^2$

Can we say that the weights show greater variation than the heights?

The sum of squares of deviations for $10$ observations taken from mean $50$ is $250$. The coefficient of variation is.....$\%$

The frequency distribution:
$\begin{array}{|l|l|l|l|l|l|l|} \hline X & A & 2 A & 3 A & 4 A & 5 A & 6 A \\ \hline f & 2 & 1 & 1 & 1 & 1 & 1 \\ \hline \end{array}$
where $A$ is a positive integer,has a variance of $160$. Determine the value of $A$.

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

If $v$ is the variance and $\sigma$ is the standard deviation,then