$\mathrm{20,33,39,40,50,53,59,65,69}$
Median, $M$ $={\left(\frac{9+1}{2}\right)}^{\mathrm{t}\mathrm{h}}$ observation $=5^{\mathrm{t}\mathrm{h}}$ observation $=50$
The absolute values of respective deviations from the median is
$\mathrm{30,17,11,10,0},\mathrm{3,9},\mathrm{15,19}$
$\therefore {\sum }_{i=1}^9\left|x_i-M\right|=114$
Mean deviation about $M=\frac{1}{9}{\sum }_{i=1}^9\left|x_i-M\right|=\frac{1}{9}\times 114$

i.e $\lambda =\frac{114}{9}\Rightarrow \frac{9\lambda }{10}=11.4$