Find the mean deviation about median for the following data:
We make the following table and add other columns after calculations.
The class interval containing or 25th item is 20-30. Therefore, 20-30 is the median class.
Now, we know that
Median
Here, l = 20, C = 14, f = 14, h = 10 and N = 50
Therefore, Median
So, we can calculate the absolute values of the deviations from the median, i.e., |xi – Med.|, as shown in the table.
Therefore, we have
And
Hence, the mean deviation about the median for the given data is 10.34.