Question

Find average for following discrete series.

X	3	5	6	7	8
f	2	4	3	8	10

Answer 1

X	f	fX
3 5 6 7 8	2 4 3 8 10	6 20 18 56 80
	N=Σf= 27	ΣfX= 180

Calculating average for the above discrete series:

$\overline{X}=\frac{\Sigma fX}{\Sigma f}$

$$\begin{gathered} \overline{X}=\frac{180}{27} \\ \Rightarrow \overline{X}=6.66 \end{gathered}$$

Thus, the average of the above series is 6.66