Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
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Chapter 7, Problem 48SE
The article “Distributions of Compressive Strength Obtained from Various Diameter Cores” (ACI Materials J., 2012: 597–606) described a study in which compressive strengths were determined for concrete specimens of various types, core diameters, and length-to-diameter ratios. For one particular type, diameter, and l/d ratio, the 18 tested specimens resulted in a sample
- a. Calculate a confidence interval with confidence level 98% for the true average compressive strength under these circumstances.
- b. Calculate a 98% lower prediction bound for the compressive strength of a single future specimen tested under the given circumstances. [Hint: t.02,17 = 2.224.]
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Chapter 7 Solutions
Probability and Statistics for Engineering and the Sciences
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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