Bundle: Modern Business Statistics with Microsoft Office Excel, Loose-Leaf Version, 6th + MindTap Business Statistics, 2 terms (12 months) Printed Access Card
6th Edition
ISBN: 9781337589383
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: Cengage Learning
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Textbook Question
Chapter 3, Problem 5CP
Although millions of elephants once roamed across Africa, by the mid-1980s elephant populations in African nations had been devastated by poaching. Elephants are important to African ecosystems. In tropical forests, elephants create clearings in the canopy that encourage new tree growth. In savannas, elephants reduce bush cover to create an environment that is favorable to browsing and grazing animals. In addition, the seeds of many plant species depend on passing through an elephant’s digestive tract before germination.
The status of the elephant now varies greatly across the continent; in some nations, strong measures have been taken to effectively protect elephant populations, while in other nations the elephant populations remain in danger due to poaching for meat and ivory, loss of habitat, and conflict with humans. Table 3.13 shows elephant populations for several African nations in 1979, 1989, and 2007 (Lemieux and Clarke, “The International Ban on Ivory Sales and Its Effects on Elephant Poaching in Africa,” British Journal of Criminology, 49(4), 2009).
The David Sheldrick Wildlife Trust was established in 1977 to honor the memory of naturalist David Leslie William Sheldrick, who founded Warden of Tsavo East National Park in Kenya and headed the Planning Unit of the Wildlife Conservation and Management Department in that country. Management of the Sheldrick Trust would like to know what these data indicate about elephant populations in various African countries since 1979.
TABLE 3.13 ELEPHANT POPULATIONS FOR SEVERAL AFRICAN NATIONS IN 1979, 1989, AND 2007
Managerial Report
Use methods of
- 1. The
mean annual change in elephant population for each country in the 10 years from 1979 to 1989, and a discussion of which countries saw the largest changes in elephant population over this 10-year period. - 2. The mean annual change in elephant population for each country from 1989 to 2007, and a discussion of which countries saw the largest changes in elephant population over this 18-year period.
- 3. A comparison of your results from parts 1 and 2, and a discussion of the conclusions you can draw from this comparison.
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Question 4
An article in Quality Progress (May 2011, pp. 42-48) describes the use of factorial experiments to improve a
silver powder production process. This product is used in conductive pastes to manufacture a wide variety of
products ranging from silicon wafers to elastic membrane switches. Powder density (g/cm²) and surface area
(cm/g) are the two critical characteristics of this product. The experiments involved three factors: reaction
temperature, ammonium percentage, stirring rate. Each of these factors had two levels, and the design was
replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
(RPM)
Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
(°C)
Density
Surface Area
100
8
14.68
0.40
100
8
15.18
0.43
30
100
8
15.12
0.42
30
100
17.48
0.41
150
7.54
0.69
150
8
6.66
0.67
30
150
8
12.46
0.52
30
150
8
12.62
0.36
100
40
10.95
0.58
100
40
17.68
0.43
30
100
40
12.65
0.57
30
100
40
15.96
0.54
150
40
8.03
0.68
150
40
8.84
0.75
30
150…
Chapter 3 Solutions
Bundle: Modern Business Statistics with Microsoft Office Excel, Loose-Leaf Version, 6th + MindTap Business Statistics, 2 terms (12 months) Printed Access Card
Ch. 3.1 - 1. Consider a sample with data values of 10, 20,...Ch. 3.1 - 2. Consider a sample with data values of 10, 20,...Ch. 3.1 - 3. Consider the following data and corresponding...Ch. 3.1 - Prob. 4ECh. 3.1 - Prob. 5ECh. 3.1 - Prob. 6ECh. 3.1 - 7. The average number of minutes Americans commute...Ch. 3.1 - Middle-Level Manager Salaries. Suppose that an...Ch. 3.1 - 9. Which companies spend the most money on...Ch. 3.1 - Advertising Spending. Which companies spend the...
Ch. 3.1 - Prob. 11ECh. 3.1 -
The Big Bang Theory, a situation comedy...Ch. 3.1 - Automobile Fuel Efficiencies. In automobile...Ch. 3.1 -
The data contained in the DATAfile named...Ch. 3.1 - 15. Martinez Auto Supplies has retail stores...Ch. 3.1 - 16. The grade point average for college students...Ch. 3.1 - 17. The following table shows the total return and...Ch. 3.1 - 18. Based on a survey of master’s programs in...Ch. 3.1 - Annual revenue for Corning Supplies grew by 5.5%...Ch. 3.1 - Suppose that at the beginning of Year 1 you...Ch. 3.1 - Prob. 21ECh. 3.1 - Prob. 22ECh. 3.2 - 23. Consider a sample with data values of 10, 20,...Ch. 3.2 - Prob. 24ECh. 3.2 - Consider a sample with data values of 27, 25, 20,...Ch. 3.2 - Price of Unleaded Gasoline. Data collected by the...Ch. 3.2 - Round-Trip Flight Prices. The following table...Ch. 3.2 -
The Australian Open is the first of the four...Ch. 3.2 - Air Quality Index. The Los Angeles Times regularly...Ch. 3.2 - Prob. 30ECh. 3.2 -
The results of Accounting Principals’ latest...Ch. 3.2 - Advertising Spend by Companies. Advertising Age...Ch. 3.2 - Scores turned in by an amateur golfer at the...Ch. 3.2 - Consistency of Running Times. The following times...Ch. 3.3 - 35. Consider a sample with data values of 10, 20,...Ch. 3.3 - 36. Consider a sample with a mean of 500 and a...Ch. 3.3 - 37. Consider a sample with a mean of 30 and a...Ch. 3.3 - 38. Suppose the data have a bell-shaped...Ch. 3.3 - 39. The results of a national survey showed that...Ch. 3.3 - 40. The energy information Administration reported...Ch. 3.3 - 41. The Graduate Management Admission Test (GMAT)...Ch. 3.3 - 42. Many families in California are using backyard...Ch. 3.3 -
According to a Los Angeles Times study of more...Ch. 3.3 - NCAA Basketball Game Scores. A sample of 10 NCAA...Ch. 3.3 -
The Wall Street Journal reported that Walmart...Ch. 3.4 - Consider a sample with data values of 27, 25, 20,...Ch. 3.4 - Prob. 47ECh. 3.4 - Prob. 48ECh. 3.4 - Prob. 49ECh. 3.4 - Naples Half-Marathon Times. Naples, Florida, hosts...Ch. 3.4 - Pharmaceutical Company Sales. Annual sales, in...Ch. 3.4 - Cell Phone Companies Customer Satisfaction....Ch. 3.4 - Most Admired Companies. Fortune magazine’s list of...Ch. 3.4 - Prob. 54ECh. 3.5 - Five observations taken for two variables...Ch. 3.5 - Prob. 56ECh. 3.5 - The DATAfile TwoStocks contains adjusted monthly...Ch. 3.5 - Driving Speed and Fuel Efficiency. A department of...Ch. 3.5 - Smoke Detector Use and Death Rates. Over the past...Ch. 3.5 - Stock Market Indexes Comparison. The Russell 1000...Ch. 3.5 - Best Private Colleges. A random sample of 30...Ch. 3 - Americans Dining Out. Americans tend to dine out...Ch. 3 - NCAA Football Coaches Salaries. A 2017 USA Today...Ch. 3 - Physician Office Waiting Times. The average...Ch. 3 - Worker Productivity and Insomnia. U.S. companies...Ch. 3 -
A study of smartphone users shows that 68% of...Ch. 3 - Work Commuting Methods. Public transportation and...Ch. 3 - Household Incomes. The following data represent a...Ch. 3 - Restaurant Chains’ Sales per Store. The data...Ch. 3 - Prob. 70SECh. 3 - NFL Teams Worth. In 2014, the 32 teams in the...Ch. 3 - MLB Team Winning Percentages. Does a major league...Ch. 3 - 73. The days to maturity for a sample of five...Ch. 3 - 74. Automobiles traveling on a road with a posted...Ch. 3 - Annual Returns for Panama Railroad Company Stock....Ch. 3 - Pelican Stores, a division of National Clothing,...Ch. 3 -
The motion picture industry is a competitive...Ch. 3 - The pursuit of a higher education degree in...Ch. 3 - Although millions of elephants once roamed across...
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