Chapter 3 Review Answer Key:
1)
a) x bar = 28
2)
a) Min = 0.2, Q1 = 0.5, Median = 0.75, Q3 = 1.65, Max = 3.2
b) x bar = 1.125, median = 0.75, mean is larger
c) range = 3, s = 0.90
3)
a) Min = 15, Q1 = 24, Median = 45, Q3 = 70, Max = 195, IQR = 46
b) Class width = 61
c) x bar = 61.1
s = 34.6
4)
a) 85.77
5)
Don’t worry about!
6)
a) x bar = 4.53, median = 4.05, mode = 1.9
b) s = 2.46, CV = 54.4, range = 6.7
7)
a) x bar = 2.15
8)
a) Min = 38, Q1 = 49, Median = 55, Q3 = 60, Max = 66
b) x bar = 53.3, median = 55. mode = 60
c) True for the mean and median, but not the mode.
9)
b) 1.88% - 10.14%
10)
x bar = 44.4
11)
a) x bar = 29 median = 26.5 mode = 27
b) range = 33 s = 11.06
a) μ = 437, median = 432
b) no mode
c) range = 260
d) σ = 80.4
12)
b) s = 20.2
b) 82.17
b) s = 2.4
c) 0.02% - 12.7%
s = 11.8
13)
a) It is possible for the range and standard deviation to be the same. For instance,
for data values that are all the same, such as 1,1,1,1,1, and 1, the range and standard
deviation are both zero.
b) It is possible for the mean, median, and mode to be all the same. For instance,
the data set1,2,3,3,3,4,5 has mean, median, and mode all of 3. The averages can all be
different, as in data set 1,2,3,3. In this case, the mean is 2.25, the median is 2.5, and the
mode is 3.
14)
a) Zapper x bar = 0.94, Zonker z bar = 1.14
b) Zapper s = 0.074, Zonker s = 0.19
c) The Zapper had better average time with a smaller standard deviation,
indicating that Zapper performed more consistently.