Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
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Question
Chapter 6.8, Problem 12E
a.
To determine
Identify the given hypotheses test is one tailed or two tailed test.
b.
To determine
Find the null hypothesis.
c.
To determine
Check whether the null hypothesis is rejected at 1% level or not.
d.
To determine
Find the 98% confidence interval for
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Check out a sample textbook solutionStudents have asked these similar questions
In testing hypotheses, which of the following would be strong evidence against the null hypothesis?a. Obtaining data with a test statistic of small magnitude.b. Obtaining data with a small P-value.c. Obtaining data with a large P-value.d. Using a large level of significance, α.e. Using a small level of significance, α
Which of the following would result in a larger width for a confidence interval?
A- use a larger sample
B- select a smaller % confidence
C- obtaining a sample with large variability
D- none of the above
Consider the following results for independent random samples taken from two populations.
Sample 1
Sample 2
n 1 = 10
n 2 = 30
x 1 = 22.5
x 2 = 20.3
s 1 = 2.1
s 2 = 4.9
What is the point estimate of the difference between the two population means (to 1 decimal)?
What is the degrees of freedom for the t distribution (round down your answer to nearest whole number)?
At 95% confidence, what is the margin of error (to 1 decimal)?
What is the 95% confidence interval for the difference between the two population means (to 1 decimal)?
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. 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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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