Solution:-

Draw a table of the given data and append other columns after calculations.

The sum of calculated data,

N = \[\sum\limits_{i=1}^{5}{{{f}_{i}}}=80\], \[\sum\limits_{i=1}^{5}{{{f}_{i}}{{x}_{i}}}=4000\]

Find mean by using the below formula

\[\overline{x}\]  =\[\frac{1}{N}\sum\limits_{i=1}^{5}{{{f}_{i}}{{x}_{i}}}=\frac{4000}{80}\]= \[50\]

From the table, \[\sum\limits_{i=1}^{5}{{{f}_{i}}\left| {{x}_{i}}-\overline{x} \right|}=1280\]

Therefore, mean deviation = \[\frac{1}{N}\sum\limits_{i=1}^{5}{{{f}_{i}}\left| {{x}_{i}}-\overline{x} \right|}\]

=\[(1/80)\times 1280\]

=\[16\]

Therefore, the mean deviation about the mean is \[16\]