Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 6.4, Problem 5E
The article “Influence of Penetration Rate on Penetrometer Resistance” (G. Gagnon and J. Doubrough, Canadian Journal of Civil Engineering, 2011:741–750) describes a study in which twenty 2-L specimens of water were drawn from a public works building in Bridgewater, Nova Scotia. The
- a. The Health Canada guideline states that the concentration should be less than 10μg/L. Can you conclude that the water in this system meets the guideline?
- b. A stricter guideline is being considered, which would require the concentration to be less than 7.5 μg/L. Can you conclude that the water in this system meets this guideline?
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Chapter 6 Solutions
Statistics for Engineers and Scientists
Ch. 6.1 - In an experiment to measure the lifetimes of parts...Ch. 6.1 - A simple random sample consists of 65 lengths of...Ch. 6.1 - The article Supply Voltage Quality in Low-Voltage...Ch. 6.1 - The pH of an acid solution used to etch aluminum...Ch. 6.1 - Recently many companies have been experimenting...Ch. 6.1 - A certain type of stainless steel powder is...Ch. 6.1 - When it is operating properly, a chemical plant...Ch. 6.1 - Lasers can provide highly accurate measurements of...Ch. 6.1 - The article Predicting Profit Performance for...Ch. 6.1 - A new concrete mix is being designed to provide...
Ch. 6.1 - Fill in the blank: If the null hypothesis is H0: ...Ch. 6.1 - Fill in the blank: In a test of H0: 10 versus...Ch. 6.1 - An engineer takes a large number of independent...Ch. 6.1 - The following MINITAB output presents the results...Ch. 6.1 - The following MINITAB output presents the results...Ch. 6.2 - For which P-value is the null hypothesis more...Ch. 6.2 - Prob. 2ECh. 6.2 - If P = 0.01, which is the best conclusion? i. H0...Ch. 6.2 - If P = 0.50, which is the best conclusion? i. H0...Ch. 6.2 - True or false: If P = 0.02, then a. The result is...Ch. 6.2 - George performed a hypothesis test. Luis checked...Ch. 6.2 - The article The Effect of Restricting Opening...Ch. 6.2 - Let be the radiation level to which a radiation...Ch. 6.2 - In each of the following situations, state the...Ch. 6.2 - The installation of a radon abatement device is...Ch. 6.2 - It is desired to check the calibration of a scale...Ch. 6.2 - A machine that fills cereal boxes is supposed to...Ch. 6.2 - A method of applying zinc plating to steel is...Ch. 6.2 - Fill in the blank: A 95% confidence interval for...Ch. 6.2 - Refer to Exercise 14. For which null hypothesis...Ch. 6.2 - A scientist computes a 90% confidence interval to...Ch. 6.2 - The strength of a certain type of rubber is tested...Ch. 6.2 - A shipment of fibers is not acceptable if the mean...Ch. 6.2 - Refer to Exercise 17. It is discovered that the...Ch. 6.2 - Refer to Exercise 18. It is discovered that the...Ch. 6.2 - The following MINITAB output (first shown in...Ch. 6.3 - Integrated circuits consist of electric channels...Ch. 6.3 - The article HIV-positive Smokers Considering...Ch. 6.3 - Do bathroom scales tend to underestimate a persons...Ch. 6.3 - The article Evaluation of Criteria for Setting...Ch. 6.3 - In a survey of 500 residents in a certain town,...Ch. 6.3 - Prob. 6ECh. 6.3 - In a sample of 150 households in a certain city,...Ch. 6.3 - Prob. 8ECh. 6.3 - Let A and B represent two variants (alleles) of...Ch. 6.3 - Prob. 10ECh. 6.3 - Refer to Exercise 2 in Section 5.2. Can it be...Ch. 6.3 - The following MINITAB output presents the results...Ch. 6.3 - Prob. 13ECh. 6.4 - Each of the following hypothetical data sets...Ch. 6.4 - A geologist is making repeated measurements (in...Ch. 6.4 - A new centrifugal pump is being considered for an...Ch. 6.4 - A certain manufactured product is supposed to...Ch. 6.4 - The article Influence of Penetration Rate on...Ch. 6.4 - A new process for producing a type of novolac...Ch. 6.4 - Specifications call for the wall thickness of...Ch. 6.4 - As part of the quality-control program for a...Ch. 6.4 - The article Approximate Methods for Estimating...Ch. 6.4 - Refer to Exercise 12 in Section 5.3. Can you...Ch. 6.4 - Refer to Exercise 13 in Section 5.3. Can you...Ch. 6.4 - The following MINITAB output presents the results...Ch. 6.4 - The following MINITAB output presents the results...Ch. 6.5 - The article Capillary Leak Syndrome in Children...Ch. 6.5 - The article Some Parameters of the Population...Ch. 6.5 - The article Measurement of Complex Permittivity of...Ch. 6.5 - The article Wired: Energy Drinks, Jock Identity,...Ch. 6.5 - In a test to compare the effectiveness of two...Ch. 6.5 - Prob. 6ECh. 6.5 - A statistics instructor who teaches a lecture...Ch. 6.5 - Fifty specimens of a new computer chip were tested...Ch. 6.5 - Are low-fat diets or low-carb diets more effective...Ch. 6.5 - In a certain supermarket, a sample of 60 customers...Ch. 6.5 - The National Opinion Research Center polled a...Ch. 6.5 - Prob. 12ECh. 6.5 - Prob. 13ECh. 6.6 - Two extrusion machines that manufacture steel rods...Ch. 6.6 - Resistors labeled as 100 are purchased from two...Ch. 6.6 - The article A Music Key Detection Method Based on...Ch. 6.6 - Prob. 4ECh. 6.6 - The article HIV-positive Smokers Considering...Ch. 6.6 - Prob. 6ECh. 6.6 - To test the effectiveness of protective packaging,...Ch. 6.6 - Prob. 8ECh. 6.6 - The article Factors Associated with Exercise...Ch. 6.6 - Prob. 10ECh. 6.6 - Prob. 11ECh. 6.6 - In a study conducted by the U.S. Department of...Ch. 6.6 - Prob. 13ECh. 6.6 - Prob. 14ECh. 6.6 - Prob. 15ECh. 6.7 - A crayon manufacturer is comparing the effects of...Ch. 6.7 - In a study of the relationship of the shape of a...Ch. 6.7 - The article Influence of Penetration Rate on...Ch. 6.7 - The article Time Series Analysis for Construction...Ch. 6.7 - The Mastic tree (Pistacia lentiscus) is used in...Ch. 6.7 - Two weights, each labeled as weighing 100 g, are...Ch. 6.7 - It is thought that a new process for producing a...Ch. 6.7 - The article Effects of Aerosol Species on...Ch. 6.7 - The article Wind-Uplift Capacity of Residential...Ch. 6.7 - The article Magma Interaction Processes Inferred...Ch. 6.7 - The article Structural Performance of Rounded...Ch. 6.7 - The article Variance Reduction Techniques:...Ch. 6.7 - In an experiment to test the effectiveness of a...Ch. 6.7 - Prob. 14ECh. 6.7 - Prob. 15ECh. 6.7 - Prob. 16ECh. 6.7 - The following MINITAB output presents the results...Ch. 6.8 - The article Improved Bioequivalence Assessment of...Ch. 6.8 - The article Estimation of Mean Arterial Pressure...Ch. 6.8 - Prob. 3ECh. 6.8 - Prob. 4ECh. 6.8 - Prob. 5ECh. 6.8 - Prob. 6ECh. 6.8 - Prob. 7ECh. 6.8 - The article Effect of Granular Subbase Thickness...Ch. 6.8 - A crossover trial is a type of experiment used to...Ch. 6.8 - Prob. 10ECh. 6.8 - Prob. 11ECh. 6.8 - Prob. 12ECh. 6.8 - Prob. 13ECh. 6.9 - The article Wastewater Treatment Sludge as a Raw...Ch. 6.9 - Prob. 2ECh. 6.9 - The article Reaction Modeling and Optimization...Ch. 6.9 - Prob. 4ECh. 6.9 - Prob. 5ECh. 6.9 - Prob. 6ECh. 6.9 - A new postsurgical treatment is being compared...Ch. 6.9 - Prob. 8ECh. 6.9 - In a comparison of the effectiveness of distance...Ch. 6.9 - Prob. 10ECh. 6.10 - Fasteners are manufactured for an application...Ch. 6.10 - At an assembly plant for light trucks, routine...Ch. 6.10 - Prob. 3ECh. 6.10 - Prob. 4ECh. 6.10 - The article Chronic Beryllium Disease and...Ch. 6.10 - The article The Effectiveness of Child Restraint...Ch. 6.10 - For the given table of observed values,...Ch. 6.10 - For the given table of observed values, a....Ch. 6.10 - Fill in the blank: For observed and expected...Ch. 6.10 - Because of printer failure, none of the observed...Ch. 6.10 - Plates are evaluated according to their surface...Ch. 6.10 - The article Determination of Carboxyhemoglobin...Ch. 6.10 - Prob. 13ECh. 6.10 - Prob. 14ECh. 6.11 - A random sample of size 11 from a normal...Ch. 6.11 - A random sample of size 29 from a normal...Ch. 6.11 - Scores on an IQ test are normally distributed. A...Ch. 6.11 - A machine that fills beverage cans is supposed to...Ch. 6.11 - A sample of 25 one-year-old girls had a mean...Ch. 6.11 - Prob. 6ECh. 6.11 - Scores on the math SAT are normally distributed. A...Ch. 6.11 - One of the ways in which doctors try to determine...Ch. 6.11 - Prob. 9ECh. 6.11 - Find the upper 1% point of F2,5.Ch. 6.11 - Prob. 11ECh. 6.11 - A broth used to manufacture a pharmaceutical...Ch. 6.11 - Refer to Exercise 11 in Section 5.6. Can you...Ch. 6.11 - Prob. 14ECh. 6.12 - A hypothesis test is performed, and the P-value is...Ch. 6.12 - A process for a certain type of ore is designed to...Ch. 6.12 - A new braking system is being evaluated for a...Ch. 6.12 - A test is made of the hypotheses H0: 10 versus...Ch. 6.12 - A vendor claims that no more than 10% of the parts...Ch. 6.12 - Prob. 6ECh. 6.12 - A new process is being considered for the...Ch. 6.13 - A test has power 0.90 when = 15. True or false:...Ch. 6.13 - A test has power 0.80 when = 3.5. True or false:...Ch. 6.13 - If the sample size remains the same, and the level...Ch. 6.13 - If the level remains the same, and the sample...Ch. 6.13 - A tire company claims that the lifetimes of its...Ch. 6.13 - A copper smelting process is supposed to reduce...Ch. 6.13 - Prob. 7ECh. 6.13 - A new process for producing silicon wafers for...Ch. 6.13 - Prob. 9ECh. 6.13 - Prob. 10ECh. 6.13 - Prob. 11ECh. 6.14 - An agricultural scientist tests six types of...Ch. 6.14 - Prob. 2ECh. 6.14 - Six different settings are tried on a machine to...Ch. 6.14 - Prob. 4ECh. 6.14 - Twenty formulations of a coating are being tested...Ch. 6.14 - Prob. 6ECh. 6.14 - Each day for 200 days, a quality engineer samples...Ch. 6 - Exercises 1 to 4 describe experiments that require...Ch. 6 - Exercises 1 to 4 describe experiments that require...Ch. 6 - Exercises 1 to 4 describe experiments that require...Ch. 6 - Exercises 1 to 4 describe experiments that require...Ch. 6 - Suppose you have purchased a filling machine for...Ch. 6 - Prob. 6SECh. 6 - Prob. 7SECh. 6 - Twenty-one independent measurements were taken of...Ch. 6 - There is concern that increased industrialization...Ch. 6 - Prob. 10SECh. 6 - A machine that grinds valves is set to produce...Ch. 6 - Resistors for use in a certain application are...Ch. 6 - A machine manufactures bolts that are supposed to...Ch. 6 - Electric motors are assembled on four different...Ch. 6 - Refer to Exercise 14. The process engineer notices...Ch. 6 - Consider the following two samples:...Ch. 6 - Prob. 17SECh. 6 - Prob. 18SECh. 6 - Two different chemical formulations of rocket fuel...Ch. 6 - Prob. 20SECh. 6 - Prob. 21SECh. 6 - The article Valuing Watershed Quality Improvements...Ch. 6 - Anthropologists can estimate the birthrate of an...Ch. 6 - Prob. 24SE
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