3.6 Mean Using Frequency

For grouped data

Working hours (x)	Employee (f)	fx
2	2	4
3	2	6
5	3	15
8	2	10
9	1	9
	\(\sum f =10\)	\(\sum fx = 50\)

\(\therefore \bar x = \frac{\sum fx}{\sum f} =\frac{50}{10}=5\)