Mathematics - Statistics Question with Solution | TestHub

Given observations are $125,a,b,170,190,210,230$.

Median$=170$

Mean deviation about median is $\frac{205}{7}$.

$\Rightarrow \frac{205}{7}=\frac{0+45+60+20+40+170-a+170-b}{7}$

$\Rightarrow a+b=300$

Mean $=\frac{170+125+230+190+210+a+b}{7}=175$

Mean deviation about mean $=\frac{50+175-a+175-b+5+15+35+55}{7}$

$=30$