Connect Access Card for Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073518237
Author: William Navidi
Publisher: McGraw-Hill Education
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Chapter 5.6, Problem 7E
During the spring of 1999, many fuel storage facilities in Serbia were destroyed by bombing. As a result, significant quantities of oil products were spilled and burned, resulting in soil pollution. The article “Mobility of Heavy Metals Originating from Bombing of Industrial Sites” (B. Škrbić, J. Novaković, and N. Miljević, Journal of Environmental Science and Health, 2002:7–16) reports measurements of heavy metal concentrations at several industrial sites in June 1999, just after the bombing, and again in March of 2000. At the Smederevo site, on the banks of the Danube River, eight soil specimens taken in 1999 had an average lead concentration (in mg/kg) of 10.7 with a standard deviation of 3.3. Four specimens taken in 2000 had an average lead concentration of 33.8 with a standard deviation of 0.50. Find a 95% confidence interval for the increase in lead concentration between June 1999 and March 2000.
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During the spring of 1999, many fuel storage facilities in Serbia were destroyed by bombing. As a result, significant quantities of oil products were spilled and burned,resulting in soil pollution. The article “Mobility of Heavy Metals Originating from Bombing of Industrial Sites” (B. Škrbić, J. Novaković, and N. Miljević, Journal of Environmental Science and Health, 2002:7–16) reports measurements of heavy metal concentrations at several industrial sites in June 1999, just after the bombing, and again in March of 2000. At the Smederevo site, on the banks of the Danube River, eight soil specimens taken in 1999 had an average lead concentration (in mg/kg) of 10.7 with a standard deviation of 3.3. Four specimens taken in 2000 had an average lead concentration of 33.8 with a standard deviation of 0.50. Find a 95% confidence interval for the increase in lead concentration between June 1999 and March 2000.
An article in Knee Surgery, Sports Traumatology, Arthroscopy, "Arthroscopic meniscal repair with an absorbable screw: results and surgical technique," (2005, Vol. 13, pp. 273-279) cites a success rate of 1% for meniscal tears with a rim width of less than 3 mm, and a 1% success rate for tears from 3-6 mm. If you are unlucky enough to suffer a meniscal tear of less than 3 mm on your left knee, and one of width 3-6 mm on your right knee, what is the probability that you have exactly one successful surgery? assume surgieries are independent.
The authors of the paper "Dynamics of Canopy Structure and Light Interception in Pinus elliottii, North Florida" (Ecological Monographs (1991):33-51) planned an experiment to determine the effect of fertilizer on a measure of leaf area. A number of plots were available for the study, and half were selected at random to be fertilized. In order to assure that the plots to receive the fertilizer and the control plots were similar, prior to beginning the experiment tree density (the number of trees per hectare) was recorded for six plots to be fertilized and six control plots, resulting in the given data. Do the plots differ in tree number? Do you have any concerns about their experimental design?
Fertilizer plots
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control plots
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Chapter 5 Solutions
Connect Access Card for Statistics for Engineers and Scientists
Ch. 5.1 - Find the value of Z/2 to use in expression (5.1)...Ch. 5.1 - Find the levels of the confidence intervals that...Ch. 5.1 - As the confidence level goes up, the reliability...Ch. 5.1 - The article Modeling Arterial Signal Optimization...Ch. 5.1 - In a sample of 100 steel wires the average...Ch. 5.1 - The article Application of Surgical Navigation to...Ch. 5.1 - The capacities (in ampere-hours) were measured for...Ch. 5.1 - Oven thermostats were tested by setting them to...Ch. 5.1 - In a sample of 80 ten-penny nails, the average...Ch. 5.1 - In a sample of 60 electric motors, the average...
Ch. 5.1 - The sugar content in a one-cup serving of a...Ch. 5.1 - Refer to Exercise 5. a. Find a 95% lower...Ch. 5.1 - Prob. 13ECh. 5.1 - Prob. 14ECh. 5.1 - Prob. 15ECh. 5.1 - Refer to Exercise 9. a. Find a 90% upper...Ch. 5.1 - Refer to Exercise 10. a. Find a 98% lower...Ch. 5.1 - Refer to Exercise 11. a. Find a 95% upper...Ch. 5.1 - Prob. 19ECh. 5.1 - A 95% confidence interval for a population mean is...Ch. 5.1 - Based on a large sample of capacitors of a certain...Ch. 5.1 - Sixty-four independent measurements were made of...Ch. 5.1 - A large box contains 10,000 ball bearings. A...Ch. 5.1 - Prob. 24ECh. 5.1 - Prob. 25ECh. 5.1 - Prob. 26ECh. 5.2 - In a simple random sample of 70 automobiles...Ch. 5.2 - During a recent drought, a water utility in a...Ch. 5.2 - A soft-drink manufacturer purchases aluminum cans...Ch. 5.2 - The article HIV-positive Smokers Considering...Ch. 5.2 - The article The Functional Outcomes of Total Knee...Ch. 5.2 - Refer to Exercise 1. Find a 95% lower confidence...Ch. 5.2 - Refer to Exercise 2. Find a 98% upper confidence...Ch. 5.2 - Refer to Exercise 4. Find a 99% lower confidence...Ch. 5.2 - A random sample of 400 electronic components...Ch. 5.2 - Refer to Exercise 9. A device will be manufactured...Ch. 5.2 - When the light turns yellow, should you stop or go...Ch. 5.2 - In a random sample of 150 customers of a...Ch. 5.2 - A sociologist is interested in surveying workers...Ch. 5.2 - Stainless steels can be susceptible to stress...Ch. 5.2 - The article A Music Key Detection Method Based on...Ch. 5.2 - A stock market analyst notices that in a certain...Ch. 5.3 - Find the value of tn1,/2 needed to construct a...Ch. 5.3 - Find the value of tn1, needed to construct an...Ch. 5.3 - Find the level of a two-sided confidence interval...Ch. 5.3 - True or false: The Students t distribution may be...Ch. 5.3 - The article Wind-Uplift Capacity of Residential...Ch. 5.3 - Prob. 6ECh. 5.3 - The article An Automatic Visual System for Marble...Ch. 5.3 - A chemist made eight independent measurements of...Ch. 5.3 - Six measurements are taken of the thickness of a...Ch. 5.3 - Fission tracks are trails found in uranium-bearing...Ch. 5.3 - The article Effect of Granular Subbase Thickness...Ch. 5.3 - The article Influence of Penetration Rate on...Ch. 5.3 - Prob. 13ECh. 5.3 - Prob. 14ECh. 5.3 - Prob. 15ECh. 5.3 - The concentration of carbon monoxide (CO) in a gas...Ch. 5.3 - The article Filtration Rates of the Zebra Mussel...Ch. 5.4 - To study the effect of curing temperature on shear...Ch. 5.4 - The article Some Parameters of the Population...Ch. 5.4 - The article Inconsistent Health Perceptions for US...Ch. 5.4 - The article Hatching Distribution of Eggs Varying...Ch. 5.4 - The article Automatic Filtering of Outliers in RR...Ch. 5.4 - A group of 78 people enrolled in a weight-loss...Ch. 5.4 - In experiments to determine the effectiveness of...Ch. 5.4 - A stress analysis was conducted on random samples...Ch. 5.4 - In a study to compare two different corrosion...Ch. 5.4 - An electrical engineer wishes to compare the mean...Ch. 5.4 - In a study of the effect of cooling rate on the...Ch. 5.4 - Refer to Exercise 11. Ten more welds will be made...Ch. 5.4 - The article The Prevalence of Daytime Napping and...Ch. 5.4 - The article Occurrence and Distribution of...Ch. 5.5 - In a test of the effect of dampness on electric...Ch. 5.5 - The specification for the pull strength of a wire...Ch. 5.5 - Angioplasty is a medical procedure in which an...Ch. 5.5 - Prob. 4ECh. 5.5 - Prob. 5ECh. 5.5 - Prob. 6ECh. 5.5 - In a study of contamination at landfills...Ch. 5.5 - Prob. 8ECh. 5.5 - A mobile computer network consists of a number of...Ch. 5.5 - The article Evaluation of Criteria for Setting...Ch. 5.5 - In a certain year, there were 80 days with...Ch. 5.6 - In a study comparing various methods of gold...Ch. 5.6 - Prob. 2ECh. 5.6 - In an experiment involving the breaking strength...Ch. 5.6 - A new post-surgical treatment is being compared...Ch. 5.6 - The article Differences in Susceptibilities of...Ch. 5.6 - The article Tibiofemoral Cartilage Thickness...Ch. 5.6 - During the spring of 1999, many fuel storage...Ch. 5.6 - Prob. 8ECh. 5.6 - The article Toward a Lifespan Metric of Reading...Ch. 5.6 - Prob. 10ECh. 5.6 - Measurements of the sodium content in samples of...Ch. 5.6 - Prob. 12ECh. 5.6 - Prob. 13ECh. 5.6 - In the article Bactericidal Properties of Flat...Ch. 5.6 - Prob. 15ECh. 5.7 - The article Simulation of the Hot Carbonate...Ch. 5.7 - The article Effect of Refrigeration on the...Ch. 5.7 - Transepidermal water loss (TEWL) is a measure of...Ch. 5.7 - Breathing rates, in breaths per minute, were...Ch. 5.7 - A group of five individuals with high blood...Ch. 5.7 - A sample of 10 diesel trucks were run both hot and...Ch. 5.7 - For a sample of nine automobiles, the mileage (in...Ch. 5.7 - Prob. 8ECh. 5.7 - Prob. 9ECh. 5.7 - Prob. 10ECh. 5.8 - Find the following values. a. 12,.0252 b. 12,.9752...Ch. 5.8 - Prob. 2ECh. 5.8 - Construct a 99% confidence interval for the...Ch. 5.8 - Prob. 4ECh. 5.8 - Scores on an IQ test are normally distributed. A...Ch. 5.8 - Prob. 6ECh. 5.8 - Boxes of cereal are labeled as containing 14...Ch. 5.8 - Prob. 8ECh. 5.8 - Following are interest rates (annual percentage...Ch. 5.8 - Prob. 10ECh. 5.8 - Prob. 11ECh. 5.8 - Prob. 12ECh. 5.9 - A sample of 25 resistors, each labeled 100, had an...Ch. 5.9 - Prob. 2ECh. 5.9 - The article Ozone for Removal of Acute Toxicity...Ch. 5.9 - Six measurements were made of the concentration...Ch. 5.9 - Five measurements are taken of the octane rating...Ch. 5 - A molecular biologist is studying the...Ch. 5 - Prob. 2SECh. 5 - The article Genetically Based Tolerance to...Ch. 5 - A sample of 87 glass sheets has a mean thickness...Ch. 5 - Prob. 5SECh. 5 - Prob. 6SECh. 5 - Leakage from underground fuel tanks has been a...Ch. 5 - Prob. 8SECh. 5 - Prob. 9SECh. 5 - Prob. 10SECh. 5 - In the article Groundwater Electromagnetic Imaging...Ch. 5 - Prob. 12SECh. 5 - Prob. 13SECh. 5 - Prob. 14SECh. 5 - A metallurgist makes several measurements of the...Ch. 5 - In a study of the lifetimes of electronic...Ch. 5 - The temperature of a certain solution is estimated...Ch. 5 - Prob. 18SECh. 5 - Prob. 19SECh. 5 - The answer to Exercise 19 part (d) is needed for...Ch. 5 - The carbon content (in ppm) was measured for each...Ch. 5 - Diameters, in mm, were measured for eight...Ch. 5 - A sample of eight repair records for a certain...Ch. 5 - Prob. 25SE
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