Let $v_1$ be the variance of $\{13, 16, 19, \dots, 103\}$ and $v_2$ be the variance of $\{20, 26, 32, \dots, 200\}$. Then the ratio $v_1 : v_2$ is:

What is the formula for finding the coefficient of variation,given $\sigma = \text{standard deviation}$ and $\bar{x} = \text{mean} \neq 0$?

In a distribution of $10$ observations,the sum of the observations is $60$ and the sum of their squares is $1000$. Then,the variance is:

If the variance of the data $2, 4, 5, 6, 8, 17$ is $23.33$,then the variance of $4, 8, 10, 12, 16, 34$ will be

Let $x_{i} (1 \leq i \leq 10)$ be ten observations of a random variable $X$. If $\sum_{i=1}^{10} (x_{i} - p) = 3$ and $\sum_{i=1}^{10} (x_{i} - p)^{2} = 9$,where $0 \neq p \in R$,then the standard deviation of these observations is:

If the standard deviation of the first $n$ natural numbers is $2$,then the value of $n$ is