An Introduction to Statistical Methods and Data Analysis
7th Edition
ISBN: 9781305269477
Author: R. Lyman Ott, Micheal T. Longnecker
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
thumb_up100%
Chapter 6.9, Problem 7E
An industrial engineer conjectures that a major difference between successful and unsuccessful companies is the percentage of their manufactured products returned because of defectives. In a study to evaluate this conjecture, the engineer surveyed the quality control departments of 50 successful companies (identified by the annual profit statement) and 50 unsuccessful companies. The companies in the study all produced products of a similar nature and cost. The percentages of the total output returned by customers in the previous year are provided in following table.
- a. Do the data provide sufficient evidence that successful businesses have a lower percentage of their products returned by customers? Use α = .05.
- b. Do the required conditions for applying your test in part (a) appear to be valid?
- c. In order for the difference in percentage returns to have an economical impact, the difference must be at least 5%. Is there significant evidence that the percentage for successful businesses is at least 5% less that the percentage for unsuccessful businesses?
- d. Estimate the difference in the percentages of returns for successful and unsuccessful businesses using a 95% confidence interval.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
PEER REPLY 1:
Choose a classmate's Main Post.
1. Indicate a range of values for the independent variable (x) that is reasonable
based on the data provided.
2. Explain what the predicted range of dependent values should be based on
the range of independent values.
In a company with 80 employees, 60 earn $10.00 per hour and 20 earn $13.00 per
hour.
Is this average hourly wage considered representative?
The following is a list of questions answered correctly on an exam. Calculate the
Measures of Central Tendency from the ungrouped data list.
NUMBER OF QUESTIONS ANSWERED CORRECTLY ON AN APTITUDE EXAM
112
72
69
97
107
73
92
76
86
73
126
128
118
127
124
82
104
132
134
83
92
108
96
100
92
115
76
91
102
81
95
141
81
80
106
84
119
113
98
75
68
98
115
106
95
100
85
94
106
119
Chapter 6 Solutions
An Introduction to Statistical Methods and Data Analysis
Ch. 6.9 - Refer to the oil-spill case study.
What are the...Ch. 6.9 - For each of the situations, set up the rejection...Ch. 6.9 - Conduct a test of H0 : μ1 μ2 – 2.3 versus Ha : μ1...Ch. 6.9 - In an effort to link cold environments with...Ch. 6.9 - The Department of Natural Resources (DNR) received...Ch. 6.9 - An industrial engineer conjectures that a major...Ch. 6.9 - The number of households currently receiving a...Ch. 6.9 - Prob. 9ECh. 6.9 - Refer to Exercise 6.11. There appears to be a...Ch. 6.9 - A firm has a generous but rather complicated...
Ch. 6.9 - Prob. 14ECh. 6.9 - Random samples of size n1 = 8 and n2 = 8 were...Ch. 6.9 - Prob. 16ECh. 6.9 - Prob. 17ECh. 6.9 - The paper Serum Beta-2-Microglobulin (SB2M) in...Ch. 6.9 - Prob. 19ECh. 6.9 - Prob. 20ECh. 6.9 - Prob. 21ECh. 6.9 - Prob. 22ECh. 6.9 - A random sample of eight pairs of twins was...Ch. 6.9 - Refer to the data of Exercise 6.11. A potential...Ch. 6.9 - Researchers are studying two existing coatings...Ch. 6.9 - Prob. 27ECh. 6.9 - The paper “Effect of Long-Term Blood Pressure...Ch. 6.9 - A study was designed to measure the effect of home...Ch. 6.9 - Prob. 30ECh. 6.9 - A random sample of eight pairs of twins were...Ch. 6.9 - Refer to Exercise 6.31. a. What is the level of...Ch. 6.9 - Use the level and power values for the paired t...Ch. 6.9 - Use the level and power values for the paired t...Ch. 6.9 - A study was conducted to determine whether...Ch. 6.9 - The effect of Benzedrine on the heart rate of dogs...Ch. 6.9 - Prob. 37E
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
- The following ordered data list shows the data speeds for cell phones used by a telephone company at an airport: A. Calculate the Measures of Central Tendency using the table in point B. B. Are there differences in the measurements obtained in A and C? Why (give at least one justified reason)? 0.8 1.4 1.8 1.9 3.2 3.6 4.5 4.5 4.6 6.2 6.5 7.7 7.9 9.9 10.2 10.3 10.9 11.1 11.1 11.6 11.8 12.0 13.1 13.5 13.7 14.1 14.2 14.7 15.0 15.1 15.5 15.8 16.0 17.5 18.2 20.2 21.1 21.5 22.2 22.4 23.1 24.5 25.7 28.5 34.6 38.5 43.0 55.6 71.3 77.8arrow_forwardIn a company with 80 employees, 60 earn $10.00 per hour and 20 earn $13.00 per hour. a) Determine the average hourly wage. b) In part a), is the same answer obtained if the 60 employees have an average wage of $10.00 per hour? Prove your answer.arrow_forwardThe following ordered data list shows the data speeds for cell phones used by a telephone company at an airport: A. Calculate the Measures of Central Tendency from the ungrouped data list. B. Group the data in an appropriate frequency table. 0.8 1.4 1.8 1.9 3.2 3.6 4.5 4.5 4.6 6.2 6.5 7.7 7.9 9.9 10.2 10.3 10.9 11.1 11.1 11.6 11.8 12.0 13.1 13.5 13.7 14.1 14.2 14.7 15.0 15.1 15.5 15.8 16.0 17.5 18.2 20.2 21.1 21.5 22.2 22.4 23.1 24.5 25.7 28.5 34.6 38.5 43.0 55.6 71.3 77.8arrow_forward
- Businessarrow_forwardhttps://www.hawkeslearning.com/Statistics/dbs2/datasets.htmlarrow_forwardNC Current Students - North Ce X | NC Canvas Login Links - North ( X Final Exam Comprehensive x Cengage Learning x WASTAT - Final Exam - STAT → C webassign.net/web/Student/Assignment-Responses/submit?dep=36055360&tags=autosave#question3659890_9 Part (b) Draw a scatter plot of the ordered pairs. N Life Expectancy Life Expectancy 80 70 600 50 40 30 20 10 Year of 1950 1970 1990 2010 Birth O Life Expectancy Part (c) 800 70 60 50 40 30 20 10 1950 1970 1990 W ALT 林 $ # 4 R J7 Year of 2010 Birth F6 4+ 80 70 60 50 40 30 20 10 Year of 1950 1970 1990 2010 Birth Life Expectancy Ox 800 70 60 50 40 30 20 10 Year of 1950 1970 1990 2010 Birth hp P.B. KA & 7 80 % 5 H A B F10 711 N M K 744 PRT SC ALT CTRLarrow_forward
- Harvard University California Institute of Technology Massachusetts Institute of Technology Stanford University Princeton University University of Cambridge University of Oxford University of California, Berkeley Imperial College London Yale University University of California, Los Angeles University of Chicago Johns Hopkins University Cornell University ETH Zurich University of Michigan University of Toronto Columbia University University of Pennsylvania Carnegie Mellon University University of Hong Kong University College London University of Washington Duke University Northwestern University University of Tokyo Georgia Institute of Technology Pohang University of Science and Technology University of California, Santa Barbara University of British Columbia University of North Carolina at Chapel Hill University of California, San Diego University of Illinois at Urbana-Champaign National University of Singapore McGill…arrow_forwardName Harvard University California Institute of Technology Massachusetts Institute of Technology Stanford University Princeton University University of Cambridge University of Oxford University of California, Berkeley Imperial College London Yale University University of California, Los Angeles University of Chicago Johns Hopkins University Cornell University ETH Zurich University of Michigan University of Toronto Columbia University University of Pennsylvania Carnegie Mellon University University of Hong Kong University College London University of Washington Duke University Northwestern University University of Tokyo Georgia Institute of Technology Pohang University of Science and Technology University of California, Santa Barbara University of British Columbia University of North Carolina at Chapel Hill University of California, San Diego University of Illinois at Urbana-Champaign National University of Singapore…arrow_forwardA company found that the daily sales revenue of its flagship product follows a normal distribution with a mean of $4500 and a standard deviation of $450. The company defines a "high-sales day" that is, any day with sales exceeding $4800. please provide a step by step on how to get the answers in excel Q: What percentage of days can the company expect to have "high-sales days" or sales greater than $4800? Q: What is the sales revenue threshold for the bottom 10% of days? (please note that 10% refers to the probability/area under bell curve towards the lower tail of bell curve) Provide answers in the yellow cellsarrow_forward
- Find the critical value for a left-tailed test using the F distribution with a 0.025, degrees of freedom in the numerator=12, and degrees of freedom in the denominator = 50. A portion of the table of critical values of the F-distribution is provided. Click the icon to view the partial table of critical values of the F-distribution. What is the critical value? (Round to two decimal places as needed.)arrow_forwardA retail store manager claims that the average daily sales of the store are $1,500. You aim to test whether the actual average daily sales differ significantly from this claimed value. You can provide your answer by inserting a text box and the answer must include: Null hypothesis, Alternative hypothesis, Show answer (output table/summary table), and Conclusion based on the P value. Showing the calculation is a must. If calculation is missing,so please provide a step by step on the answers Numerical answers in the yellow cellsarrow_forwardShow all workarrow_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
Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Functions and Change: A Modeling Approach to Coll...
Algebra
ISBN:9781337111348
Author:Bruce Crauder, Benny Evans, Alan Noell
Publisher:Cengage Learning
Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt
Hypothesis Testing using Confidence Interval Approach; Author: BUM2413 Applied Statistics UMP;https://www.youtube.com/watch?v=Hq1l3e9pLyY;License: Standard YouTube License, CC-BY
Hypothesis Testing - Difference of Two Means - Student's -Distribution & Normal Distribution; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=UcZwyzwWU7o;License: Standard Youtube License