The mean deviation about the median is $..........$

If $M_1$ is the mean deviation from the mean of the discrete data $44, 5, 27, 20, 8, 54, 9, 14, 35$ and $M_2$ is the mean deviation from the median of the same data,then $M_1 - M_2 =$

Calculate the mean deviation about the mean of the set of first $n$ natural numbers when $n$ is an even number.

$\begin{aligned} &\text{Find the mean deviation about the mean for the following data:} \\ &\begin{array}{|l|c|c|c|c|c|} \hline \text{Class Interval} & 0-6 & 6-12 & 12-18 & 18-24 & 24-30 \\ \hline \text{Frequency} & 1 & 2 & 3 & 2 & 1 \\ \hline \end{array} \end{aligned}$

Calculate the mean deviation about the median age for the age distribution of $100$ persons given below:

Age (in years)	$16-20$	$21-25$	$26-30$	$31-35$	$36-40$	$41-45$	$46-50$	$51-55$
Number of persons	$5$	$6$	$12$	$14$	$26$	$12$	$16$	$9$

The mean deviation from the mean for the data $6, 7, 10, 12, 13, 4, 12, 16$ is