Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
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Chapter 3, Problem 12SE
The article “Effect of Varying Solids Concentration and Organic Loading on the Performance of Temperature Phased Anaerobic Digestion Process” (S. Vandenburgh and T. Ellis, Water Environment Research, 2002:142–148) discusses experiments to determine the effect of the solids concentration on the performance of treatment methods for wastewater sludge. In the first experiment, the concentration of solids (in g/L) was 43.94 ± 1.18. In the second experiment, which was independent of the first, the concentration was 48.66 ± 1.76. Estimate the difference in the concentration between the two experiments, and find the uncertainty in the estimate.
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The article “Effect of Varying Solids Concentration and Organic Loading on the Performance of Temperature Phased Anaerobic Digestion Process” (S. Vandenburgh and T. Ellis, Water Environment Research, 2002:142–148) discusses experiments to determine the effect of the solids concentration on the performance of treatment methods for wastewater sludge. In the first experiment, the concentration of solids (in g/L) was 43.94 ± 1.18. In the second experiment, which was independent of the first, the concentration was 48.66 ± 1.76. Estimate the difference in the concentration between the two experiments, and find the uncertainty in the estimate.
The article “Hydrogeochemical Characteristics of Groundwater in a Mid-Western CoastalAquifer System” (S. Jeen, J. Kim, et al., Geosciences Journal, 2001:339–348) presentsmeasurements of various properties of shallow groundwater in a certain aquifer system inKorea. Following are measurements of electrical conductivity (in microsiemens percentimeter) for 23 water samples.2099 528 2030 1350 1018 384 14991265 375 424 789 810 522 513488 200 215 486 257 557 260461 500Find the mean.Find the standard deviation.Find the median.Construct a dotplot.Find the 10% trimmed mean.Find the first quartile.Find the third quartile.Find the interquartile range.Construct a boxplot.Which of the points, if any, are outliers?If a histogram were constructed, would it be skewed to the left, skewed to the right, orapproximately symmetric?
Researchers interested in lead exposure due to car exhaust sampled the blood of 52 police officers subjected to constant inhalation of automobile exhaust fumes while working traffic enforcement in a primarily urban environment. The blood samples of these officers had an average lead concentration of 124.32 µg/l and an SD of 37.74 µg/l; a previous study of individuals from a nearby suburb, with no history of exposure, found an average blood level concentration of 35 µg/l.
Write down the hypotheses that would be appropriate for testing if the police officers appear to have been exposed to a higher concentration of lead.
Explicitly state and check all conditions necessary for inference on these data.
Test the hypothesis that the downtown police officers have a higher lead exposure than the group in the previous study. Interpret your results in context.
Based on your preceding result, without performing a calculation, would a 99% confidence interval for the average blood concentration…
Chapter 3 Solutions
Statistics for Engineers and Scientists
Ch. 3.1 - The boiling point of water is measured four times....Ch. 3.1 - Two thermometers are calibrated by measuring the...Ch. 3.1 - The weight of an object is given as 67.2 0.3 g....Ch. 3.1 - Prob. 4ECh. 3.1 - A person stands on a bathroom scale. The reading...Ch. 3.1 - A person gets on and off a bathroom scale four...Ch. 3.1 - In a hypothetical scenario, the National Institute...Ch. 3.1 - Prob. 8ECh. 3.1 - A new and unknown weight is weighed on the same...Ch. 3.1 - Prob. 10E
Ch. 3.1 - The length of a rod was measured eight times. The...Ch. 3.2 - Assume that X and Y are independent measurements...Ch. 3.2 - The length of a rod is to be measured by a process...Ch. 3.2 - The volume of a cone is given by V = r2h/3, where...Ch. 3.2 - In the article The Worlds Longest Continued Series...Ch. 3.2 - A cylindrical hole is bored through a steel block,...Ch. 3.2 - A force of F = 2.2 0.1 N is applied to a block...Ch. 3.2 - The period T of a simple pendulum is given by...Ch. 3.2 - The specific gravity of a substance is given by G...Ch. 3.2 - Prob. 10ECh. 3.2 - According to Newtons law of cooling, the...Ch. 3.2 - Prob. 12ECh. 3.2 - Nine independent measurements are made of the...Ch. 3.2 - A certain scale has an uncertainty of 3 g and a...Ch. 3.2 - The volume of a rock is measured by placing the...Ch. 3.2 - A student measures the spring constant k of a...Ch. 3.2 - A certain chemical process is run 10 times at a...Ch. 3.2 - An object is weighed four times, and the results,...Ch. 3.2 - Prob. 19ECh. 3.2 - Prob. 20ECh. 3.3 - Find the uncertainty in Y, given that X = 2.0 0.3...Ch. 3.3 - Given that X and Y are related by the given...Ch. 3.3 - The volume of a cone is given by V = r2h/3, where...Ch. 3.3 - Prob. 4ECh. 3.3 - The period T of a simple pendulum is given by...Ch. 3.3 - The change in temperature of an iron bar brought...Ch. 3.3 - The friction velocity F of water flowing through a...Ch. 3.3 - The refractive index n of a piece of glass is...Ch. 3.3 - The density of a rock will be measured by placing...Ch. 3.3 - The conversion of ammonium cyanide to urea is a...Ch. 3.3 - Prob. 11ECh. 3.3 - Prob. 12ECh. 3.3 - The acceleration g due to gravity is estimated by...Ch. 3.3 - Refer to Exercise 4. Assume that T = 298.4 0.2 K....Ch. 3.3 - Refer to Exercise 5. a. Assume g = 9.80 m/s2...Ch. 3.3 - Refer to Exercise 6. Assume that c = 448 J/kgC and...Ch. 3.3 - Prob. 17ECh. 3.3 - Refer to Exercise 8. Assume the critical angle is...Ch. 3.3 - Refer to Exercise 9. Assume that the mass of the...Ch. 3.3 - Prob. 20ECh. 3.4 - Find the uncertainty in U, assuming that X = 10.0 ...Ch. 3.4 - The volume of a cone is given by V = r2h/3, where...Ch. 3.4 - From a fixed point on the ground, the distance to...Ch. 3.4 - Refer to Exercise 10 in Section 3.2. Assume that ...Ch. 3.4 - When air enters a compressor at pressure P1 and...Ch. 3.4 - One way to measure the water content of a soil is...Ch. 3.4 - Prob. 7ECh. 3.4 - Prob. 8ECh. 3.4 - The Beer-Lambert law relates the absorbance A of a...Ch. 3.4 - In the article Temperature-Dependent Optical...Ch. 3.4 - Refer to Exercise 12 in Section 3.2. Assume that 0...Ch. 3.4 - Prob. 12ECh. 3.4 - Archaeologists studying meat storage methods...Ch. 3.4 - Prob. 14ECh. 3.4 - A cylindrical wire of radius R elongates when...Ch. 3.4 - Prob. 16ECh. 3.4 - Refer to Exercise 16. In an experiment to...Ch. 3.4 - The vertical displacement v of a cracked slurry...Ch. 3.4 - The shape of a bacterium can be approximated by a...Ch. 3.4 - Prob. 20ECh. 3.4 - Refer to Exercise 10 in Section 3.2. Assume that ...Ch. 3.4 - Refer to Exercise 5. Assume that P1 = 15.3 0.2...Ch. 3.4 - Refer to Exercise 7. Assume that p = 4.3 0.1 cm...Ch. 3.4 - Prob. 24ECh. 3.4 - Refer to Exercise 12. Estimate n, and find the...Ch. 3.4 - Refer to Exercise 14. Assume that l = 10.0 cm ...Ch. 3.4 - Prob. 27ECh. 3.4 - Refer to Exercise 16. Assume that T0 = 73.1 0.1F,...Ch. 3.4 - Prob. 29ECh. 3.4 - Prob. 30ECh. 3.4 - Prob. 31ECh. 3 - Prob. 1SECh. 3 - Prob. 2SECh. 3 - Prob. 3SECh. 3 - Prob. 4SECh. 3 - Prob. 5SECh. 3 - Let A and B represent two variants (alleles) of...Ch. 3 - The heating capacity of a calorimeter is known to...Ch. 3 - Sixteen independent measurements were made of the...Ch. 3 - If two gases have molar masses M1 and M2, Grahams...Ch. 3 - A piece of plywood is composed of five layers. The...Ch. 3 - The article Effect of Varying Solids Concentration...Ch. 3 - Prob. 13SECh. 3 - Prob. 14SECh. 3 - Prob. 15SECh. 3 - The mean yield from process A is estimated to be...Ch. 3 - The flow rate of water through a cylindrical pipe...Ch. 3 - Prob. 18SECh. 3 - The decomposition of nitrogen dioxide (NO2) into...Ch. 3 - Prob. 20SECh. 3 - A track has the shape of a square capped on two...Ch. 3 - Prob. 22SECh. 3 - Prob. 23SE
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