Download find the coefficient of variation and compute the

Measures of Variance Worksheet
1. Given the sample data, find the range, variance, and standard deviation.
𝑥∶
2.
23
17
15
30
25
If 𝑥̅ = 15, 𝑎𝑛𝑑 𝑠 = 3, find the coefficient of variation and compute the
Chebyshev intervals.
3. For Mallard ducks and Canada geese, what percentage of nests are
successful ( at least one offspring survives ). The data below shows the
percentages of success for nests in several states.
Mallard
𝑥 ∶ 56
85
52
13
39
Geese
𝑦 ∶ 24
53
60
69
18
a) Calculate the mean, variance, and standard deviation for both.
b) Calculate the coefficient of variation for both. What do the results tell
you ?
4. Kevlar epoxy is a material used on the NASA space shuttles. Strands of this
epoxy were tested at 90% breaking strength. The following data shows time
to failure ( in hours ) for a random sample of 50 epoxy strands.
0.54
3.34
1.81
1.52
1.60
1.80
1.54
2.17
0.19
1.80
1.52
0.08
0.63
1.55
4.69
2.05
0.12
0.56
0.02
0.08
1.03
0.60
0.03
0.07
7.89
1.18
0.72
0.09
0.65
1.58
0.80
0.92
0.18
0.40
1.64
1.13
1.05
0.34
0.24
0.03
1.29
1.43
1.51
1.51
0.23
1.11
3.03
1.45
1.45
0.72
a) Find the range of the data set.
b) Compute the sample mean, variance, and standard deviation.
c) Find the coefficient of variance. What does this number say about time to
failure ?