Question

Find the mean deviation about the mean for the given data.

Q1. 4, 7, 8, 9, 10, 12, 13, 17

Answer 1

Mean of the given data is

$\overline{x}=\frac{4+7+8+9+10+12+13+17}{8}=\frac{80}{8}=10$ $\begin{array}{cc}{x}_1& |x_i-\overline{x}|\\ 4& 6\\ 7& 3\\ 8& 2\\ 9& 1\\ 10& 0\\ 12& 2\\ 13& 3\\ 17& 7\\ \text{Total}& 24\end{array}$

$\text{M.D. about mean}=\frac{1}{n}{\sum }_{i-1}^n|x_i-\overline{x}|=\frac{1}{8}\times 24$ = 3