Question

Find the mean of the following frequency distribution : 

Class	0-10	10-20	20-30	30-40	40-50
Frequency	4	7	6	3	5

Answer 1

Class Interval	Xi	fi	fiXi
0-10	5	4	20
10-20	15	7	105
20-30	25	6	150
30-40	35	3	105
40-50	45	5	225
Total		25	605

`barx =  (Σf_iX_i)/(Σ"f")`

`barx = 605/25`

`barx = 24.2`

∴ Mean = 24.2