Calculate the mean deviation from the median of the following data:

Given: the frequency distribution

To find: the mean deviation from the median

Let us make a table of the given data and append other columns after calculations

Now, here N=20, which is even.

Here median class=,

This observation lie in the class interval 12-18, so median can be written as,

Here l=12, cf=9, f=3, h=6 and N=20, substituting these values, the above equation becomes,

⇒M=12+2=14

So the above table with more columns is as shown below,

Hence Mean Deviation becomes,

Therefore, the mean deviation about the median of the distribution is 7