• Chapter 4


  •   
  • FileName: Ch4 Testbank Handout.pdf [read-online]
    • Abstract: Chapter 4Describing Data: Displaying and Exploring DataTrue/FalseMultiple Choice46. The test scores for a class of 147 students are computed. What is the location of the test scoreassociated with the third quartile?

Download the ebook

Chapter 4
Describing Data: Displaying and Exploring Data
True/False
Multiple Choice
46. The test scores for a class of 147 students are computed. What is the location of the test score
associated with the third quartile?
A) 111
B) 37
C) 74
D) 75%
Answer: A
51. Mr. and Mrs. Jones live in a neighborhood where the mean family income is $45,000 with a standard
deviation of $9,000. Mr. and Mrs. Smith live in a neighborhood where the mean is $100,000 and the
standard deviation is $30,000. What is the relative dispersion of the family incomes in the two
neighborhoods?
A) Jones 40%, Smith 20%
B) Jones 20%, Smith 30%
C) Jones 30%, Smith 20%
D) Jones 50%, Smith 33%
E) None of the above
Answer: B
52. A large oil company is studying the number of gallons of gasoline purchased per customer at self-
service pumps. The mean number of gallons is 10.0 with a standard deviation of 3.0 gallons. The median
is 10.75 gallons. What is the Pearson's coefficient of skewness?
A) -1.00
B) -0.75
C) +0.75
D) +1.00
Answer: B
53. What is the value of the Pearson coefficient of skewness for a distribution with a mean of 17, median
of 12 and standard deviation of 6?
A) +2.5
B) -2.5
C) +0.83
D) -0.83
Answer: A
Statistical Techniques in Business & Economics, Lind/Marchal/Wathen, 13/e 53
59. A sample of experienced typists revealed that their mean typing speed is 87 words per minute and the
median is 73. The standard deviation is 16.9 words per minute. What is the Pearson's coefficient of
skewness?
A) -2.5
B) -4.2
C) +4.2
D) +2.5
Answer: D
60. A study of the net sales of a sample of small corporations revealed that the mean net sales is $2.1
million, the median $2.4 million, the modal sales $2.6 million and the standard deviation of the
distribution is $500,000. What is the Pearson's coefficient of skewness?
A) -9.1
B) +6.3
C) -3.9
D) +2.4
E) None of the above
Answer: E
Fill-in-the-Blank
64. For a stem-and-leaf display, what is the stem for the value 67? ____.
Answer: 6
Essay
65. Construct a stem-and-leaf display for the following data:
29 32 37 34 38 22
33 57 21 65 35 52
46 35 54 26 55 59
22 30 38 39 31 20
69 19 58 42 50 51
Answer:
1| 9
2| 0 1 2 2 6 9
3| 0 1 2 3 4 5 5 7 8 8 9
4| 2 6
5| 0 1 2 4 5 7 8 9
6| 5 9
66. From the following stem-and-leaf display, find the minimum value, the 1st quartile, the median, the
3rd quartile, and the maximum value. List and interpret the interquartile range.
1| 9
2| 0 1 2 2 6 9
3| 0 1 2 3 4 5 5 7 8 8 9
4| 2 6
5| 0 1 2 4 5 7 8 9
6| 5 9
54 Test Bank, Chapter 4
Answer: Minimum=19, 1st quartile = 29.75, median = 37.5 , 3rd quartile = 52.5, Maximum = 69.
Interquartile range is 52.5-29.75 = 22.75. It means that 50% or 15 of the 30 observations are between
52.5 and 29.75
Fill-in-the-Blank
67. For a stem-and-leaf display, what is the leaf for the value 123? ____.
Answer: 3
68. If you are constructing a stem-and-leaf display, the "3" in 19.3 would be the ____________.
Answer: leaf
69. If you are constructing a stem-and-leaf display, the "20" in 20.5 would be the _____________.
Answer: stem
71. What is the main advantage of a stem-and-leaf chart over a histogram? ___________________
Answer: The identity of each observation is not lost
76. If the mean of a distribution is smaller than the median and mode, what is the sign of Pearson's
coefficient of skewness? _______________
Answer: negative
78. For a set of data, how many quartiles are there? _____
Answer: three
79. If two sets of data are measured in different units, what statistic can be used to compare their
dispersions? ___________________________________
Answer: coefficient of variation
80. What unit of measurement is used to express the coefficient of variation? _________
Answer: percent
81. The coefficient of variation is a measure of _______________.
Answer: relative dispersion
82. The research director of a large oil company conducted a study of the buying habits of consumers
with respect to the amount of gasoline purchased at full-service pumps. The arithmetic mean amount is
11.5 gallons and the median amount is 11.95 gallons. The standard deviation of the sample is 4.5 gallons.
What is the Pearson's coefficient of skewness? ________
Answer: -0.30
84. The annual incomes of the five vice presidents of Elly's Industries are: $41,000, $38,000, $32,000,
$33,000 and $50,000. The annual incomes of Unique, another firm similar to Elly's Industries, were also
studied and found to have a mean of $38,900 and a standard deviation of $6,612. What company has the
greater coefficient of variation? ______________
Answer: Elly, (19.0) > Unique (17.0)
86. The lengths of stay on the cancer floor of Community Hospital were organized into a frequency
distribution. The mean length was 28 days, the median 25 days and the modal length 23 days. The
Statistical Techniques in Business & Economics, Lind/Marchal/Wathen, 13/e 55
standard deviation was computed to be 4.2 days. What is the Pearson's coefficient of skewness?
__________
Answer: 2.14
87. A sample of the homes currently offered for sale revealed that the mean asking price is $75,900, the
median $70,100 and the modal price is $67,200. The standard deviation of the distribution is $5,900.
What is the Pearson's coefficient of skewness? __________
Answer: 2.95
88. The Pearson's coefficient of skewness (Sk) measures the amount of skewness and may range from -
3.0 to +3.0. It is computed by subtracting the median from the mean, multiplying the result by 3 and
dividing by? ________________
Answer: standard deviation
Essay
89. Given the sample information in the following table regarding public opinion on gun control, who is
more likely to favor gun control?
Opinion on Gun Control
Party Affiliation Favor Oppose No opinion Total
Democrat 90 98 46 234
Republican 90 54 10 154
Total 180 152 56 388
Answer: Republicans are more likely to favor gun control with 58% favoring gun control. Only 38% of
democrats favor gun control.
Fill-in-the-Blank
Use the following to answer questions 90-94:
A telemarketing firm is monitoring the performance of its employees based on the number of sales per
hour. One employee had the following sales for the last 20 hours
9 5 2 6 5 6 4 4 4 7
4 4 7 8 4 4 5 5 4 8
90. What is the median for the distribution of number of sales per hour? ____________
Answer: Median = 5 sales per hour
91. What is the first quartile for the distribution of number of sales per hour? ________________
Answer: Q1 = 4 sales per hour
92. What is the third quartile for the distribution of number of sales per hour? _____________
Answer: Q3 = 6.5 sales per hour
93. For the distribution of number of sales per hour, 50% are greater than ____________
Answer: The median or 5 sales per hour
56 Test Bank, Chapter 4
94. For the distribution of number of sales per hour, 50% of the observations are between __________
and ____________.
Answer: Q1 (4) and Q3 (6.5)
Use the following to answer questions 95-101:
The following stem and leaf display reports the number of boat shipments per week by Ottertail Boats,
Inc.
11| 1 5 9
12| 0 1 2 2 6 9
13| 0 1 2 3 4 5 5 7 8 8 9
14| 2 6 8
15| 0 1 2 4 5 7 8 9
16| 1 5 7 9
95. How many weeks were included in the study?____________
Answer: 35 weeks
96. How many observations are in the third class?__________
Answer: 11 weeks
97. What are the smallest and largest values?___________
Answer: 111 and 169 orders
98. List the actual values in the fourth class._______________
Answer: 142, 146, and 148 orders
99. How often did the company complete 111 shipments? ____________
Answer: 1 or once
100. How often did the company complete more than 140 shipments? __________
Answer: 15 times
101. What is the median value? _______________
Answer: 138 shipments,
Essay
102. What is the common purpose of a scatter diagram and a contingency table?
Answer: Both are used to summarize two variables:
103. What is the difference between a scatter diagram and a contingency table?
Answer: A scatter diagram requires interval or ratio scaled variables, a contingency table requires
nominal or ordinal variables.
Statistical Techniques in Business & Economics, Lind/Marchal/Wathen, 13/e 57


Use: 0.013