Chapter 3 - Section 3.2 - Measures of Dispersion for Ungrouped Data - Exercises - Page 97: 3.40

a. range = 181, variance = 3287.538 standard deviation = 57.3371 b. coefficient of variation = 21.71%

a. range = 357 - 176 = 181 $Variance = Variance = σ^2=[∑(x-μ)^2 ]/n-1 $ $={∑(x^2) –[∑(x)^2/N]}/n-1$ $=(873043-836880)/11$ $= 3287.54$ Standard Deviation = $\sqrt 3287.54= 57.3371$ b. Coefficient of Variation=$57.3371\div264.83\times100=21.71%$