Range is 26.3
Variance is 119.20
Standard deviation is 10.9
The higher values for range, variance, and standard deviation indicate a wide spread in the salary data.
What is variance?
Given
Dataset: 39 38 37 30 20 18 17 14 13.6 12.7
a) Range is the highest - the smallest
Range = 39 - 12.7 = 26.3.
b) variance = Σ(x - xbar)²/n-1
n = 10
xbar = mean
xbar = 39+38+37+30+20+18+17+14+13.6+12.7/10
= 239.3/10 = 23.93
Variance = (39-23.93)²+(38-23.93)²+(37-23.93)²+(30-23.93)²+(20-23.93)²+(18-23.93)²+(27-23.93)²+(14-23.93)²+(13.6-23.93)²+(12.7-23.93)²/10-1
= 227.105+197.965+170.825+36.845+15.445+35.165+48.025+98.605+106.709+126.113
= 1072.822/9 = 119.20
The variance of the data is 119.20
c) Standard deviation = √variance
S.D = √119.20 = 10.9
The consistent values for range, variance, and standard deviation in the provided top 10 TV personalities' salaries indicate significant variation, reflecting a wide spread in salaries of TV personalities.