If the mean and variance of six observations $7,10,11,15,a,b$ are $10$ and $\frac{20}{3},$ respectively, then the value of $|a-b|$ is equal to:

Q. The mean and variance of $7$ observations are $8$ and $16$, respectively. If five observations are $2,4,10,12,14,$ then the absolute difference of the remaining two observations is:

Q.

The mean and variance of eight observations are 9 and 9.25 respectively. If six of the observations are 6, 7, 10, 12, 12 and 13, find the remaining two observations

Q. If mean and standard deviation of $5$ observations $x_1,x_2,x_3,x_4,x_5$ are $10$ and $3$, respectively, then the variance of $6$ observations $x_1,x_2,....,x_5$ and $-50$ is equal to :

Q. The mean and variance of $20$ observations are found to be $10$ and $4$ respectively. On rechecking, it was found that an observation which was $11$ was incorrectly recorded as $9$. If the correct variance is $V$, then the value of $\left[V\right]$ is

Q. If mean and standard deviation of $5$ observations $x_1,x_2,x_3,x_4,x_5$ are $10$ and $3$, respectively, then the variance of $6$ observations $x_1,x_2,\cdots ,x_5$ and $-50$ is equal to :