Find the mean deviation about the median for the following continuous distribution

$\frac{N}{2}=25$ cumulative frequency just $>\frac{N}{2}\text{ is }28,$

Observation lies in the class interval 20-30 this is median class

Median $=L+\left[\frac{\frac{N}{2}-m}{f}\right]h=20+\left\{\frac{25-14}{14}\right\}10=20+7.857=27.857$

Mean deviation about median $=\frac{1}{N}\sum _{i=1}^6 f_i\mid x_i-\text{ Median }\mid =\frac{1}{50}\left(517.1\right)=10.34$