Student Solutions Manual for Devore's Probability and Statistics for Engineering and the Sciences, 9th
9th Edition
ISBN: 9798214004020
Author: Jay L. Devore
Publisher: Cengage Learning US
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Chapter 7, Problem 56SE
The accompanying data on crack initiation depth (μm) was read from a lognormal probability plot that appeared in the article “Incorporating Small Fatigue Crack Growth in Probabilistic Life Prediction: Effect of Stress Ratio in Ti-6Al-2Sn-6Mo” (Intl. J. of Fatigue, 2013: 83–95). Although the pattern in the plot was quite straight, a normal probability plot of the data also shows a reasonably linear pattern. And a boxplot indicates that the distribution is quite symmetric in the middle 50% of the data and only mildly skewed overall. It is therefore reasonable to estimate and predict using t intervals.
- a. Estimate the true average crack initiation depth with a 99% CI and interpret the resulting interval.
- b. Predict the value of a single crack initiation depth by constructing a 99% PI.
- c. Interpret in context the meaning of 99% in (b).
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An article in Environment International ["influence of Water Temperature and Shower
Head Office Size on the release Radon During Showering" (1992, Vol. 18(4)] described an
experiment in which the amount of radon released in showers was imvestigated. Radon-enriched
water was used in the experiment, and six different orifice diameters were tested in shower
heads. The data from the experiment are shown in the following table.
5.
Orifice Diameter
0.37
0.51
0.71
1.02
Radon Released ()
83
75
73
72
83
85
79
79
74
76
77
67
74
74
1.40
62
62
67
69
1.99
60
64
66
(a) Does the size of the orifice affect the mean percentage of radon released? Use a=0.05.
(b) Find a 95% confidence interval on the mean percent of radon released when the orifice
diameter is 1.40.
The article “Monte Carlo Simulation—Tool for Better Understanding of LRFD” (J. of Structural Engr., 1993: 1586–1599) suggests that yield strength (ksi) for A36 grade steel is normally distributed with mean = 43 and standard deviation = 4.5.(a) What is the probability that yield strength is greater than 58?
(b) What yield strength value separates the strongest 75% from the others?
Chapter 7 Solutions
Student Solutions Manual for Devore's Probability and Statistics for Engineering and the Sciences, 9th
Ch. 7.1 - Consider a normal population distribution with the...Ch. 7.1 - Each of the following is a confidence interval for...Ch. 7.1 - Suppose that a random sample of 50 bottles of a...Ch. 7.1 - A CI is desired for the true average stray-load...Ch. 7.1 - Assume that the helium porosity (in percentage) of...Ch. 7.1 - On the basis of extensive tests, the yield point...Ch. 7.1 - By how much must the sample size n be increased if...Ch. 7.1 - Let 1 0, 2 0, with 1 + 2 = . Then P(z1X-/nz2)=1-...Ch. 7.1 - a. Under the same conditions as those leading to...Ch. 7.1 - A random sample of n = 15 heat pumps of a certain...
Ch. 7.1 - Consider the next 1000 95% CIs for that a...Ch. 7.2 - The following observations are lifetimes (days)...Ch. 7.2 - The article Gas Cooking. Kitchen Ventilation, and...Ch. 7.2 - The negative effects of ambient air pollution on...Ch. 7.2 - Determine the confidence level for each of the...Ch. 7.2 - The alternating current (AC) breakdown voltage of...Ch. 7.2 - Exercise 1.13 gave a sample of ultimate tensile...Ch. 7.2 - The U.S. Army commissioned a study to assess how...Ch. 7.2 - The article Limited Yield Estimation for Visual...Ch. 7.2 - TV advertising agencies face increasing challenges...Ch. 7.2 - In a sample of 1000 randomly selected consumers...Ch. 7.2 - The technology underlying hip replacements has...Ch. 7.2 - The Pew Forum on Religion and Public Life reported...Ch. 7.2 - A sample of 56 research cotton samples resulted in...Ch. 7.2 - The Pew Forum on Religion and Public Life reported...Ch. 7.2 - The superintendent of a large school district,...Ch. 7.2 - Reconsider the CI (7.10) for p, and focus on a...Ch. 7.3 - Determine the values of the following quantities:...Ch. 7.3 - Determine the t critical value(s) that will...Ch. 7.3 - Determine the t critical value for a two-sided...Ch. 7.3 - Determine the t critical value for a lower or an...Ch. 7.3 - According to the article Fatigue Testing of...Ch. 7.3 - The article Measuring and Understanding the Aging...Ch. 7.3 - A sample of 14 joint specimens of a particular...Ch. 7.3 - Silicone implant augmentation rhinoplasty is used...Ch. 7.3 - A normal probability plot of the n = 26...Ch. 7.3 - A study of the ability of individuals to walk in a...Ch. 7.3 - Ultra high performance concrete (UHPC) is a...Ch. 7.3 - Exercise 72 of Chapter 1 gave the following...Ch. 7.3 - Prob. 40ECh. 7.3 - A more extensive tabulation of t critical values...Ch. 7.4 - Determine the values of the following quantities:...Ch. 7.4 - Determine the following: a. The 95th percentile of...Ch. 7.4 - The amount of lateral expansion (mils) was...Ch. 7.4 - Wire electrical-discharge machining (WEDM) is a...Ch. 7.4 - Wire electrical-discharge machining (WEDM) is a...Ch. 7 - Example 1.11 introduced the accompanying...Ch. 7 - The article Distributions of Compressive Strength...Ch. 7 - For those of you who dont already know, dragon...Ch. 7 - A journal article reports that a sample of size 5...Ch. 7 - Unexplained respiratory symptoms reported by...Ch. 7 - High concentration of the toxic element arsenic is...Ch. 7 - Aphid infestation of fruit trees can be controlled...Ch. 7 - It is important that face masks used by...Ch. 7 - A manufacturer of college textbooks is interested...Ch. 7 - The accompanying data on crack initiation depth...Ch. 7 - In Example 6.8, we introduced the concept of a...Ch. 7 - Prob. 58SECh. 7 - Prob. 59SECh. 7 - Prob. 60SECh. 7 - Prob. 61SECh. 7 - Prob. 62SE
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