Question

Find the mean:

Class interval:	0-8	8-16	16-24	24-32	32-40
Frequency:	6	7	10	8	9

Answer 1

Let’s consider the assumed mean (A) = 20

From the table it’s seen that,

A = 20 and h = 8

Mean = A + h x (\(\frac{Σf_i u_i}{N}\))

= 20 + 8 x (\(\frac{7}{40}\))

= 20 + 1.4

= 20.4