Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 6.9, Problem 8E
To determine
Check whether there is evidence to conclude that the mean strength is greater for blocks cured for six days.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
In an experiment to determine the effect of ambient temperature on the emissons of oxides of nitrogen (
NOx
) of diesel trucks,
10
trucks were run at temperatures of
40°F
and
80°F
. The emissions, in parts per billion, are presented in the following table.
Truck
40°F
80°F
1
926.5
896.7
2
851.1
857.0
3
975.5
952.1
4
1009.3
884.8
5
871.8
840.7
6
949.2
885.1
7
1006.3
885.5
8
836.5
777.8
9
837.8
850.2
10
958.9
882.1
Send data to Excel
Let
μ1
represent the mean emission at
40°F
and
=μd−μ1μ2
.Can you conclude that the mean emission differs between the two temperatures? Use the
=α0.05
level of significance and the TI-84 Plus calculator to answer the following.
p value ?
do we reject?
is there enough evidence :?
The owner of a new car conducts a series of six gas mileage tests and obtains the following results, expressed in miles per gallon: 3., 22.7, 21.4, 20.6, and 21.4. 20.9. Find the mode for these data.
In a test of H0:μ = 100 against Ha:μ>100, a sample of size 80 producers z = 0.8 for the value of the test statistic. The P-value of the test is thus equal to?
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
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- 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 a 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. 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 level of police officers contain 35 µg/l? Based on your preceding result, without performing a calculation, would a 99% confidence interval for this difference contain 0? Explain why or why not.arrow_forwardIn a test of H0:μ = 100 against H1:μ>100, a sample of size 80 producers z= 0.8 for the value of the test statistic. The P-value of the test is equal to?arrow_forwardThe following data pertain to x, the amount of fertil-izer (in pounds) that a farmer applies to his soil, and y, his yield of wheat (in bushels per acre): xy xy xy112 33 88 24 37 2792 28 44 17 23 972 38 132 36 77 3266 17 23 14 142 38112 35 57 25 37 1388 31 111 40 127 2342 8 69 29 88 31126 37 19 12 48 3772 32 103 27 61 2552 20 141 40 71 1428 17 77 26 113 26 Assuming that the data can be looked upon as a randomsample from a bivariate normal population, calculate rand test its significance at the 0.01 level of significance.Also, draw a scattergram of these paired data and judgewhether the assumption seems reasonable.arrow_forward
- An article includes the accompanying data on compression strength (lb) for a sample of 12-oz aluminum cans filled with strawberry drink and another sample filled with cola. Beverage Sample Size Sample Mean Sample SD Strawberry Drink 10 535 24 Cola 10 559 15 Does the data suggest that the extra carbonation of cola results in a higher average compression strength? Base your answer on a P-value. (Use ? = 0.05.) State the relevant hypotheses. (Use ?1 for the strawberry drink and ?2 for the cola.) H0: ?1 − ?2 = 0Ha: ?1 − ?2 ≥ 0H0: ?1 − ?2 = 0Ha: ?1 − ?2 ≠ 0 H0: ?1 − ?2 = 0Ha: ?1 − ?2 < 0H0: ?1 − ?2 = 0Ha: ?1 − ?2 > 0 Calculate the test statistic and determine the P-value. (Round your test statistic to one decimal place and your P-value to three decimal places.) t = P-value = State the conclusion in the problem context. Reject H0. The data suggests that cola has a higher average compression strength than the strawberry drink.Reject H0. The…arrow_forwardSix samples of each of four types of cereal grain grown in a certain region were analyzed to determine thiamin content, resulting in the following data (µg/g). Wheat 5.3 4.4 6.1 6.1 6.6 5.8 Barley 6.4 8.1 6.2 7.5 5.9 5.6 Maize 5.7 4.8 6.5 5.0 6.1 5.2 Oats 8.2 6.1 7.9 7.1 5.4 7.3 Does this data suggest that at least two of the grains differ with respect to true average thiamin content? Use a level ? = 0.05 test.State the appropriate hypotheses. H0: ?1 ≠ ?2 ≠ ?3 ≠ ?4 Ha: at least two ?i's are equal H0: ?1 = ?2 = ?3 = ?4 Ha: at least two ?i's are unequal H0: ?1 = ?2 = ?3 = ?4 Ha: all four ?i's are unequal H0: ?1 ≠ ?2 ≠ ?3 ≠ ?4 Ha: all four ?i's are equal Compute the test statistic value. (Round your answer to two decimal places.)f = What can be said about the P-value for the test? P-value > 0.100 0.050 < P-value < 0.100 0.010 < P-value < 0.050 0.001 < P-value < 0.010 P-value < 0.001 State the conclusion in the problem context. Reject H0.…arrow_forwardIn a test of H0: µ=75 against HA: µ<75, a sample of size 450 produces Z = -1.19 for the value of the test statistic. Thus the p-value is approximately equal to:arrow_forward
- Suppose that we want to compare the cholestrol contents of four competing diet foods on the basis of the following data (in milligrams per package) which were obtained for three 6-ounce packages of each of the diet foods: Diet food A: 3.6 4.1 4.0 Diet food B: 3.1 3.2 3.9 Diet food C: 3.2 3.5 3.5 Diet food D: 3.5 3.8 3.8 Fill in the blanks below. Test at the 0.05 level of significance whether the differences among means obtained for the four competing diet foods (Diet A, B, C, D) are significant? (Ftable=4.07) source of varation degrees of freedom sum of squares mean squares F treatments ? 0.54 ? ? error ? ? ? total ? 1.18arrow_forwardrofessor Cornish studied rainfall cycles and sunspot cycles. (Reference: Australian Journal of Physics, Vol. 7, pp. 334-346.) Part of the data include amount of rain (in mm) for 6-day intervals. The following data give rain amounts for consecutive 6-day intervals at Adelaide, South Australia. 7 28 7 1 69 3 1 4 22 7 16 4 54 160 60 73 27 3 3 1 7 144 107 4 91 44 1 8 4 22 4 59 116 52 4 155 42 24 11 43 3 24 19 74 26 63 110 39 34 71 52 39 8 0 15 2 14 9 1 2 4 9 6 10 (i) Find the median. (Use 1 decimal place.)(ii) Convert this sequence of numbers to a sequence of symbols A and B, where A indicates a value above the median and B a value below the median. Test the sequence for randomness about the median at the 5% level of significance. (b) Find the number of runs R, n1, and n2. Let n1 = number of values above the median and n2 = number of values below the median. R n1 n2 (c) In the case, n1 > 20, we cannot use Table 10 of Appendix II to find the critical…arrow_forwardIn a detailed study of the productivity of a laboratory, the age distribution of its workers was analyzed, and the results were as follows, the kurtosis coefficient is equal toarrow_forward
- Suppose that we want to compare the cholestrol contents of four competing diet foods on the basis of the following data (in milligrams per package) which were obtained for three 6-ounce packages of each of the diet foods: Diet food A: 3.6 4.1 4.0 Diet food B: 3.1 3.2 3.9 Diet food C: 3.2 3.5 3.5 Diet food D: 3.5 3.8 3.8 a)Fill in the blanks below. b)Test at the 0.05 level of significance whether the differences among means obtained for the four competing diet foods (Diet A, B, C, D) are significant? (Ftable=4.07) ONE-WAY ANOVA TABLE Source of Variation Degrees of Freedom Sum of Squares Mean Square F Treatments ? 0.54 ? ? Error ? ? ? Total ? 1.18arrow_forwardThe following data were obtained from a two-factor independent-measures experiment with n=10 participants in each treatment condition. B1 B2 A1 M=4 T=50 SS=20 M=7 T=20 SS=28 A2 M=1 T=20 SS=12 M=4 T=30 SS-20 a. Calculate degrees of freedom and locate the critical region for each of the three tests (a=.05) b. Calculate the three F-ratios c. State the conclusion for each test.arrow_forwardConsider the accompanying data on flexural strength (MPa) for concrete beams of a certain type. 5.3 7.2 7.3 6.3 8.1 6.8 7.0 7.1 6.8 6.5 7.0 6.3 7.9 9.0 9.0 8.7 7.8 9.7 7.4 7.7 9.7 7.9 7.7 11.6 11.3 11.8 10.7 The data below give accompanying strength observations for cylinders. 6.8 5.8 7.8 7.1 7.2 9.2 6.6 8.3 7.0 9.0 7.6 8.1 7.4 8.5 8.9 9.8 9.7 14.1 12.6 11.8 Prior to obtaining data, denote the beam strengths by X1, . . . , Xm and the cylinder strengths by Y1, . . . , Yn. Suppose that the Xi's constitute a random sample from a distribution with mean ?1 and standard deviation ?1 and that the Yi's form a random sample (independent of the Xi's) from another distribution with mean ?2 and standard deviation ?2. (a) Calculate the estimate for the given data. (Round your answer to three decimal places.) (b) Use rules of variance to obtain an expression for the variance and standard deviation (standard error) of the estimator in part (a). V(X − Y) = V(X) + V(Y) =…arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
The Shape of Data: Distributions: Crash Course Statistics #7; Author: CrashCourse;https://www.youtube.com/watch?v=bPFNxD3Yg6U;License: Standard YouTube License, CC-BY
Shape, Center, and Spread - Module 20.2 (Part 1); Author: Mrmathblog;https://www.youtube.com/watch?v=COaid7O_Gag;License: Standard YouTube License, CC-BY
Shape, Center and Spread; Author: Emily Murdock;https://www.youtube.com/watch?v=_YyW0DSCzpM;License: Standard Youtube License