Statistics
Chapter 2: Descriptive Statistics
CHAPTER 2: Descriptive Statistics
2.3
[LO 1]
28 2007 #1 28 71,273.93 58,069,987.70 7,620.37 59490 87970 28480
Distribution is skewed right.
Descriptive statistics count mean sample variance sample standard deviation minimum maximum range
Stem and Leaf plot for stem unit = leaf unit = Frequency 2 9 13 4 28
#1 10000 1000 Stem 5 6 7 8 Leaf 99 123446677 0000112444447 1377
Distribution is more normally shaped in 2007.
2.5 [LO 2] a. We have 2 6 64 and 2 7 128. Because 26 < n = 100 and 27 > n = 100, we use K = 7 classes.
Class length =
largest measurement smallest measurement 11.6 0.4 1.6 K 7
Class .4 – 1.9 2.0 – 3.5 3.6 – 5.1 5.2 – 6.7
Frequency 8 13 27 24
Relative Frequency .08 .13 .27 .24
Boundaries .35, 1.95 1.95, 3.55 3.55, 5.15 5.15, 6.75
Midpoint 1.15 2.75 4.35 5.95
Student Solutions Manual Business Statistics in Practice, Second Canadian Edition © 2011 McGraw-Hill Ryerson Limited. All rights reserved. 1
Chapter 2: Descriptive Statistics
6.8 – 8.3 8.4 – 9.9 10.0 – 11.5 11.6 – 13.1*
14 10 3 1
.14 .10 .03 .01
6.75, 8.35 8.35, 9.95 9.95, 11.5 11.55, 13.15
7.55 9.15 10.75 12.35
* Since the largest measurement is not within the seventh class, we add an eighth class.
b. 2.7
The population of all possible customer waiting times during peak business hours is somewhat positively skewed with a tail to the right.
[LO 1, 4]
Roger Maris 8 4 3 6 3 8 6 3 9 0 0 1 1 2 2 3 3 4 4 5 5 6 Babe Ruth
1
2 5 4 5 1 6 4 9 0
1 6 4
6
7
9
The 61 home runs hit by Maris would be considered an outlier, although an exceptional individual achievement.
2.13[LO 5] a b N 10 7 MEAN 20 503 MEDIAN 20 501 MODE 20 501
2.15[LO 5] a. b.
Yes, because x 6 .
5 .2 5 .3 5.25 2 The mean is slightly larger than the median. The stem-and-leaf display is somewhat skewed right. median
2.17
[LO 3, 5] a.
mean = 272.333; median = 68 (Canada’s value)
CHAPTER 2: Descriptive Statistics
2.3
[LO 1]
28 2007 #1 28 71,273.93 58,069,987.70 7,620.37 59490 87970 28480
Distribution is skewed right.
Descriptive statistics count mean sample variance sample standard deviation minimum maximum range
Stem and Leaf plot for stem unit = leaf unit = Frequency 2 9 13 4 28
#1 10000 1000 Stem 5 6 7 8 Leaf 99 123446677 0000112444447 1377
Distribution is more normally shaped in 2007.
2.5 [LO 2] a. We have 2 6 64 and 2 7 128. Because 26 < n = 100 and 27 > n = 100, we use K = 7 classes.
Class length =
largest measurement smallest measurement 11.6 0.4 1.6 K 7
Class .4 – 1.9 2.0 – 3.5 3.6 – 5.1 5.2 – 6.7
Frequency 8 13 27 24
Relative Frequency .08 .13 .27 .24
Boundaries .35, 1.95 1.95, 3.55 3.55, 5.15 5.15, 6.75
Midpoint 1.15 2.75 4.35 5.95
Student Solutions Manual Business Statistics in Practice, Second Canadian Edition © 2011 McGraw-Hill Ryerson Limited. All rights reserved. 1
Chapter 2: Descriptive Statistics
6.8 – 8.3 8.4 – 9.9 10.0 – 11.5 11.6 – 13.1*
14 10 3 1
.14 .10 .03 .01
6.75, 8.35 8.35, 9.95 9.95, 11.5 11.55, 13.15
7.55 9.15 10.75 12.35
* Since the largest measurement is not within the seventh class, we add an eighth class.
b. 2.7
The population of all possible customer waiting times during peak business hours is somewhat positively skewed with a tail to the right.
[LO 1, 4]
Roger Maris 8 4 3 6 3 8 6 3 9 0 0 1 1 2 2 3 3 4 4 5 5 6 Babe Ruth
1
2 5 4 5 1 6 4 9 0
1 6 4
6
7
9
The 61 home runs hit by Maris would be considered an outlier, although an exceptional individual achievement.
2.13[LO 5] a b N 10 7 MEAN 20 503 MEDIAN 20 501 MODE 20 501
2.15[LO 5] a. b.
Yes, because x 6 .
5 .2 5 .3 5.25 2 The mean is slightly larger than the median. The stem-and-leaf display is somewhat skewed right. median
2.17
[LO 3, 5] a.
mean = 272.333; median = 68 (Canada’s value)