The mean deviation about the mean for the observations $ -1, 0, 4 $ is:

Let $\bar{X}$ and $M.D.$ be the mean and the mean deviation about $\bar{X}$ of $n$ observations $x_i,$ $i = 1, 2, \dots, n.$ If each of the observations is increased by $5,$ then the new mean and the mean deviation about the new mean,respectively,are

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

Find the mean deviation about the mean for the following data:

Income per day	Number of persons
$0-100$	$4$
$100-200$	$8$
$200-300$	$9$
$300-400$	$10$
$400-500$	$7$
$500-600$	$5$
$600-700$	$4$
$700-800$	$3$

The mean deviation from the mean for the observations $1, 3, 5, 7, 11, 13, 17, 19, 23$ is

The mean deviation from the mean for the data $ 3, 10, 10, 4, 7, 10, 5 $ is: