Question

Question 1 Find the mean deviation about the mean for the data

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

Class X1 - Maths -Statistics Page 360

Answer 1

Mean of the given series :
we know,
mean = sum of terms /number of terms
e.g.,
$\overline{x}=\frac{\sum{x_i}}{n}$
$=\frac{4+7+8+9+10+12+13+17}{8}\\\\=\frac{80}{8}\\\\=10$
hence, mean deviation about mean,
$MD=\frac{\sum{|x_i-\overline{x}|}}{n}\\\\=\frac{24}{8}\\\\=3$