Question

Age	Frequency	Midpoint	f*M	f*(M-xbar)2
30-39	2
40-49	3
50-59	7
60-69	5
70-79	1

Compute the Coefficient of Variation to 2 decimal places.

Do NOT format answer: No $, Commas, %.

Answer 1

Mean:

Xbar =

Midpoint = (Upper Class limit + Lower class limit) / 2

For First Class:

Midpoint = (30+39)/2 = 34.5

Similarly, solve for other classess...

Computational table:

Age	Frequency (f)	Midpoint (M)	f*M	f*(M-xbar)2
30-39	2	=(30+39)/2 = 34.5	69	800
40-49	3	=(40+49)/2 = 44.5	133.5	300
50-59	7	=(50+59)/2 = 54.5	381.5	0
60-69	5	=(60+69)/2 = 64.5	322.5	500
70-79	1	=(70+79)/2 = 74.5	74.5	400
Total	18		981	2000

standard deviation (S):

Coefficient of variation (CV):

CV = (S/)*100

CV = (10.54 / 54.5)

CV = 0.19