Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
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Chapter 9.1, Problem 4E
Reliance on solid biomass fuel for cooking and heating exposes many children from developing countries to high levels of indoor air pollution. The article “Domestic Fuels, Indoor Air Pollution, and Children’s Health” (Annals of the N.Y. Academy of Sciences, 2008: 209–217) presented information on various pulmonary characteristics in samples of children whose households in India used either biomass fuel or liquefied petroleum gas (LPG). For the 755 children in biomass households, the sample
For the 750 children whose households used liquefied petroleum gas, the sample mean PEF was 4.25 and the sample standard deviation was 1.75.
a. Calculate a confidence interval at the 95% confidence level for the population mean PEF for children in biomass households and then do likewise for children in LPG households. What is the simultaneous confidence level for the two intervals?
b. Carry out a test of hypotheses at significance level .01 to decide whether true average PEF is lower for children in biomass households than it is for children in LPG households (the cited article included a P-value for this test).
c. FEV1, the forced expiratory volume in 1 second, is another measure of pulmonary
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Chapter 9 Solutions
Probability and Statistics for Engineering and the Sciences
Ch. 9.1 - An article in the November 1983 Consumer Reports...Ch. 9.1 - The National Health Statistics Reports dated Oct....Ch. 9.1 - Pilates is a popular set of exercises for the...Ch. 9.1 - Reliance on solid biomass fuel for cooking and...Ch. 9.1 - Persons having Reynauds syndrome are apt to suffer...Ch. 9.1 - An experiment to compare the tension bond strength...Ch. 9.1 - Is there any systematic tendency for part-time...Ch. 9.1 - Tensile-strength tests were carried out on two...Ch. 9.1 - The article Evaluation of a Ventilation Strategy...Ch. 9.1 - An experiment was performed to compare the...
Ch. 9.1 - The level of lead in the blood was determined for...Ch. 9.1 - The accompanying summary data on total cholesterol...Ch. 9.1 - A mechanical engineer wishes to compare strength...Ch. 9.1 - The level of monoamine oxidase (MAO) activity in...Ch. 9.1 - Prob. 15ECh. 9.1 - Prob. 16ECh. 9.2 - Determine the number of degrees of freedom for the...Ch. 9.2 - Which way of dispensing champagne, the traditional...Ch. 9.2 - Suppose 1 and 2 are true mean stopping distances...Ch. 9.2 - Use the data of Exercise 19 to calculate a 95% CI...Ch. 9.2 - Quantitative noninvasive techniques are needed for...Ch. 9.2 - According to the article Modeling and Predicting...Ch. 9.2 - Fusible interlinings are being used with...Ch. 9.2 - Damage to grapes from bird predation is a serious...Ch. 9.2 - The accompanying data consists of prices () for...Ch. 9.2 - The article The Influence of Corrosion Inhibitor...Ch. 9.2 - Anorexia Nervosa (AN) is a psychiatric condition...Ch. 9.2 - As the population ages, there is increasing...Ch. 9.2 - The article Effect of Internal Gas Pressure on the...Ch. 9.2 - The article Flexure of Concrete Beams Reinforced...Ch. 9.2 - Refer to Exercise 33 in Section 7.3. The cited...Ch. 9.2 - The degenerative disease osteoarthritis most...Ch. 9.2 - The article The Effects of a Low-Fat, Plant-Based...Ch. 9.2 - Consider the pooled t variable T=(XY)(12)sp1m+1n...Ch. 9.2 - Prob. 35ECh. 9.3 - Consider the accompanying data on breaking load...Ch. 9.3 - Prob. 37ECh. 9.3 - Adding computerized medical images to a database...Ch. 9.3 - Scientists and engineers frequently wish to...Ch. 9.3 - Lactation promotes a temporary loss of bone mass...Ch. 9.3 - Antipsychotic drugs are widely prescribed for...Ch. 9.3 - Many freeways have service (or logo) signs that...Ch. 9.3 - Cushings disease is characterized by muscular...Ch. 9.3 - Prob. 44ECh. 9.3 - Torsion during hip external rotation (ER) and...Ch. 9.3 - Example 7.11 gave data on the modulus of...Ch. 9.3 - The article Slender High-Strength RC Columns Under...Ch. 9.3 - Prob. 48ECh. 9.4 - Consider the following two questions designed to...Ch. 9.4 - Recent incidents of food contamination have caused...Ch. 9.4 - It is well known that a placebo, a fake medication...Ch. 9.4 - Do teachers find their work rewarding and...Ch. 9.4 - Olestra is a fat substitute approved by the FDA...Ch. 9.4 - Teen Court is a juvenile diversion program...Ch. 9.4 - In medical investigations, the ratio = p1/p2 is...Ch. 9.4 - Sometimes experiments involving success or failure...Ch. 9.4 - Two different types of alloy, A and B, have been...Ch. 9.4 - Prob. 58ECh. 9.5 - Obtain or compute the following quantities: a....Ch. 9.5 - Give as much information as you can about the...Ch. 9.5 - Prob. 61ECh. 9.5 - Prob. 62ECh. 9.5 - Toxaphene is an insecticide that has been...Ch. 9.5 - The following observations are on time (h) for a...Ch. 9.5 - The article Enhancement of Compressive Properties...Ch. 9.5 - Prob. 66ECh. 9 - The accompanying summary data on compression...Ch. 9 - The article Supervised Exercise Versus Non-...Ch. 9 - Is the response rate for questionnaires affected...Ch. 9 - Shoveling is not exactly a high-tech activity, but...Ch. 9 - The article Quantitative MRI and Electrophysiology...Ch. 9 - The following summary data on bending strength...Ch. 9 - Prob. 73SECh. 9 - The derailment of a freight train due to the...Ch. 9 - Prob. 75SECh. 9 - Prob. 76SECh. 9 - Information about hand posture and forces...Ch. 9 - Prob. 78SECh. 9 - The article The Accuracy of Stated Energy Contents...Ch. 9 - Arsenic is a known carcinogen and poison. The...Ch. 9 - Prob. 81SECh. 9 - Acrylic bone cement is commonly used in total...Ch. 9 - In an experiment to compare bearing strengths of...Ch. 9 - Prob. 84SECh. 9 - An experimenter wishes to obtain a CI for the...Ch. 9 - Prob. 86SECh. 9 - Prob. 87SECh. 9 - The paper Quantitative Assessment of Glenohumeral...Ch. 9 - Prob. 89SECh. 9 - Prob. 90SECh. 9 - Prob. 91SECh. 9 - Prob. 92SECh. 9 - The article Evaluating Variability in Filling...Ch. 9 - Prob. 94SECh. 9 - Prob. 95SE
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