Statistical Techniques in Business and Economics
18th Edition
ISBN: 9781260579611
Author: Douglas Lind; William Marchal; Samuel Wathen
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Question
Chapter 9, Problem 11E
(a)
To determine
To find: The value of the population
(b)
To determine
To explain: The reason for using t -distribution. Also, state the assumption that is necessary to make.
(c)
To determine
To find: The value of t .
(d)
To determine
To calculate: The margin of error for a 95% confidence interval.
(e)
To determine
To calculate: The 95% confidence interval of the population mean.
(f)
To determine
To find: If it would be reasonable to conclude that the population mean is 21 and/or 25.
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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 9 Solutions
Statistical Techniques in Business and Economics
Ch. 9 - Prob. 1SRCh. 9 - Prob. 1ECh. 9 - A sample of 81 observations is taken from a normal...Ch. 9 - Prob. 3ECh. 9 - Suppose you know and you want an 85% confldence...Ch. 9 - Prob. 5ECh. 9 - Prob. 6ECh. 9 - Prob. 7ECh. 9 - Prob. 8ECh. 9 - Prob. 2SR
Ch. 9 - Prob. 9ECh. 9 - Prob. 10ECh. 9 - Prob. 11ECh. 9 - Prob. 12ECh. 9 - Prob. 13ECh. 9 - Prob. 14ECh. 9 - Prob. 3SRCh. 9 - Prob. 15ECh. 9 - Ms. Maria Wilson is considering running for mayor...Ch. 9 - Prob. 17ECh. 9 - Prob. 18ECh. 9 - Prob. 4SRCh. 9 - Prob. 19ECh. 9 - Prob. 20ECh. 9 - Prob. 21ECh. 9 - Prob. 22ECh. 9 - Prob. 23ECh. 9 - Prob. 24ECh. 9 - Prob. 25ECh. 9 - Prob. 26ECh. 9 - The same study of church contributions in Scandia...Ch. 9 - Thirty-six items are randomly selected from a...Ch. 9 - Forty-nine items are randomly selected from a...Ch. 9 - The attendance at the Savannah Colts minor league...Ch. 9 - There are 300 welders employed at Maine Shipyards...Ch. 9 - Prob. 31CECh. 9 - Prob. 32CECh. 9 - Prob. 33CECh. 9 - Prob. 34CECh. 9 - Prob. 35CECh. 9 - Prob. 36CECh. 9 - Prob. 37CECh. 9 - Prob. 38CECh. 9 - Prob. 39CECh. 9 - Prob. 40CECh. 9 - Prob. 41CECh. 9 - Prob. 42CECh. 9 - Prob. 43CECh. 9 - Prob. 44CECh. 9 - Prob. 45CECh. 9 - Prob. 46CECh. 9 - Prob. 47CECh. 9 - Prob. 48CECh. 9 - Prob. 49CECh. 9 - Prob. 50CECh. 9 - Prob. 51CECh. 9 - Prob. 52CECh. 9 - Prob. 53CECh. 9 - Prob. 54CECh. 9 - Prob. 55CECh. 9 - Prob. 56CECh. 9 - Prob. 57CECh. 9 - Prob. 58CECh. 9 - Prob. 59CECh. 9 - Prob. 60CECh. 9 - Prob. 61CECh. 9 - Prob. 62CECh. 9 - Prob. 63CECh. 9 - Prob. 64CECh. 9 - Prob. 65CECh. 9 - Prob. 66CECh. 9 - A sample of 352 subscribers to Wired magazine...Ch. 9 - Prob. 68CECh. 9 - Prob. 69DACh. 9 - Prob. 70DACh. 9 - Prob. 71DACh. 9 - Prob. 1PCh. 9 - Prob. 2PCh. 9 - Prob. 3PCh. 9 - Prob. 4PCh. 9 - Prob. 5PCh. 9 - Prob. 6PCh. 9 - Prob. 7PCh. 9 - Prob. 8PCh. 9 - Prob. 9PCh. 9 - Prob. 10PCh. 9 - Prob. 11PCh. 9 - Prob. 12PCh. 9 - Prob. 13PCh. 9 - Prob. 1CCh. 9 - Prob. 1.1PTCh. 9 - Prob. 1.2PTCh. 9 - Prob. 1.3PTCh. 9 - Prob. 1.4PTCh. 9 - Prob. 1.5PTCh. 9 - Prob. 1.6PTCh. 9 - Prob. 1.7PTCh. 9 - Prob. 1.8PTCh. 9 - Prob. 1.9PTCh. 9 - Prob. 1.10PTCh. 9 - Prob. 2.1PTCh. 9 - Prob. 2.2PTCh. 9 - Prob. 2.3PTCh. 9 - Prob. 2.4PT
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