Elementary Statistics: A Step By Step Approach
9th Edition
ISBN: 9780073534985
Author: Allan Bluman
Publisher: McGraw-Hill Science/Engineering/Math
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Chapter 6.1, Problem 52EC
To determine
To find: The value of z for 75th percentile, 80th percentile, and 92nd percentile.
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A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A marketing professor has surveyed the students at her university to better understand attitudes towards PPT usage for higher education. To be able to make inferences to the entire student body, the sample drawn needs to represent the university’s student population on all key characteristics. The table below shows the five key student demographic variables. The professor found the breakdown of the overall student body in the university’s fact book posted online.
A non-parametric chi-square test was used to test the sample demographics against the population percentages shown in the table above. Review the output for the five chi-square tests on the following pages and answer the five questions:
Based on the chi-square test, which sample variables adequately represent the university’s student population and which ones do not? Support your answer by providing the p-value of the chi-square test and explaining what it means.
Using the results from Question 1, make recommendation for…
A retail chain is interested in determining whether a digital video point-of-purchase (POP) display would stimulate higher sales for a brand advertised compared to the standard cardboard point-of-purchase display. To test this, a one-shot static group design experiment was conducted over a four-week period in 100 different stores. Fifty stores were randomly assigned to the control treatment (standard display) and the other 50 stores were randomly assigned to the experimental treatment (digital display). Compare the sales of the control group (standard POP) to the experimental group (digital POP).
What were the average sales for the standard POP display (control group)?
What were the sales for the digital display (experimental group)?
What is the (mean) difference in sales between the experimental group and control group?
List the null hypothesis being tested.
Do you reject or retain the null hypothesis based on the results of the independent t-test?
Was the difference between the…
Chapter 6 Solutions
Elementary Statistics: A Step By Step Approach
Ch. 6.1 - Many times in statistics it is necessary to see if...Ch. 6.1 - What are the characteristics of an normal...Ch. 6.1 - Why is the standard normal distribution important...Ch. 6.1 - What is the total area under the standard normal...Ch. 6.1 - What percentage of the area falls below the mean?...Ch. 6.1 - About what percentage of the area under the normal...Ch. 6.1 - What are two other names for a normal...Ch. 6.1 - Prob. 7ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 9E
Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 11ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 13ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 17ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 21ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 23ECh. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - For Exercises 7 through 26, find the area under...Ch. 6.1 - Prob. 27ECh. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - Prob. 29ECh. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - Prob. 31ECh. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - Prob. 33ECh. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - Prob. 37ECh. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - In Exercises 27 through 40, find the probabilities...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - For Exercises 41 through 46, find the z value that...Ch. 6.1 - Find the z value to the left of the mean so that...Ch. 6.1 - Find the z value to the right of the mean so that...Ch. 6.1 - Find two z values, one positive and one negative,...Ch. 6.1 - Find two z values so that 48% of the middle area...Ch. 6.1 - Prob. 51ECCh. 6.1 - Prob. 52ECCh. 6.1 - Prob. 53ECCh. 6.1 - For Exercises 5356, z0 is the statistical notation...Ch. 6.1 - Prob. 55ECCh. 6.1 - Prob. 56ECCh. 6.1 - Prob. 57ECCh. 6.1 - Prob. 58ECCh. 6.1 - Prob. 59ECCh. 6.1 - Find P(z 2.3 and z 1.2).Ch. 6.2 - Applying the Concepts 62 Smart People Assume you...Ch. 6.2 - Prob. 1ECh. 6.2 - Teachers Salaries The average annual salary for...Ch. 6.2 - Population in U.S. Jails The average daily jail...Ch. 6.2 - SAT Scores The national average SAT score (for...Ch. 6.2 - Chocolate Bar Calories The average number of...Ch. 6.2 - Monthly Mortgage Payments The average monthly...Ch. 6.2 - Prob. 7ECh. 6.2 - Doctoral Student Salaries Full-time Ph.D. students...Ch. 6.2 - Miles Driven Annually The mean number of miles...Ch. 6.2 - Commute Time to Work The average commute to work...Ch. 6.2 - Credit Card Debt The average credit card debt for...Ch. 6.2 - Prob. 12ECh. 6.2 - Prob. 13ECh. 6.2 - Newborn Elephant Weights Newborn elephant calves...Ch. 6.2 - Prob. 15ECh. 6.2 - Salary of Full Professors The average salary of a...Ch. 6.2 - Prob. 17ECh. 6.2 - Itemized Charitable Contributions The average...Ch. 6.2 - New Home Sizes A contractor decided to build homes...Ch. 6.2 - New-Home Prices If the average price of a new...Ch. 6.2 - Cost of Personal Computers The average price of a...Ch. 6.2 - Reading Improvement Program To help students...Ch. 6.2 - Prob. 23ECh. 6.2 - Ages of Amtrak Passenger Cars The average age of...Ch. 6.2 - Lengths of Hospital Stays The average length of a...Ch. 6.2 - High School Competency Test A mandatory competency...Ch. 6.2 - Product Marketing An advertising company plans to...Ch. 6.2 - Prob. 28ECh. 6.2 - Wristwatch Lifetimes The mean lifetime of a...Ch. 6.2 - Police Academy Acceptance Exams To qualify for a...Ch. 6.2 - In the distributions shown, state the mean and...Ch. 6.2 - SAT Scores Suppose that the mathematics SAT scores...Ch. 6.2 - Prob. 33ECh. 6.2 - Standardizing If a distribution of raw scores were...Ch. 6.2 - Social Security Payments Consider the distribution...Ch. 6.2 - Find the Mean In a normal distribution, find when...Ch. 6.2 - Internet Users U.S. internet users spend an...Ch. 6.2 - Exam Scores An instructor gives a 100-point...Ch. 6.2 - Drive-in Movies The data shown represent the...Ch. 6.2 - Prob. 40ECh. 6.2 - Prob. 41ECh. 6.2 - Prob. 42ECh. 6.2 - Prob. 43ECh. 6.3 - Applying the Concepts 63 Times To Travel to School...Ch. 6.3 - Prob. 1ECh. 6.3 - Why do most of the sample means differ somewhat...Ch. 6.3 - What is the mean of the sample means?Ch. 6.3 - What is the standard deviation of the sample means...Ch. 6.3 - What does the central limit theorem say about the...Ch. 6.3 - What formula is used to gain information about an...Ch. 6.3 - Prob. 7ECh. 6.3 - Glass Garbage Generation A survey found that the...Ch. 6.3 - Prob. 9ECh. 6.3 - Teachers Salaries in Connecticut The average...Ch. 6.3 - Prob. 11ECh. 6.3 - Teachers Salaries in North Dakota The average...Ch. 6.3 - Prob. 13ECh. 6.3 - SAT Scores The national average SAT score (for...Ch. 6.3 - Cost of Overseas Trip The average overseas trip...Ch. 6.3 - Cell Phone Lifetimes A recent study of the...Ch. 6.3 - Water Use The Old Farmers Almanac reports that the...Ch. 6.3 - Medicare Hospital Insurance The average yearly...Ch. 6.3 - Amount of Laundry Washed Each Year Procter Gamble...Ch. 6.3 - Per Capita Income of Delaware Residents In a...Ch. 6.3 - Prob. 21ECh. 6.3 - Systolic Blood Pressure Assume that the mean...Ch. 6.3 - Cholesterol Content The average cholesterol...Ch. 6.3 - Ages of Proofreaders At a large publishing...Ch. 6.3 - TIMSS Test On the Trends in International...Ch. 6.3 - Life Expectancies In a study of the life...Ch. 6.3 - Home Values A study of 800 homeowners in a certain...Ch. 6.3 - Breaking Strength of Steel Cable The average...Ch. 6.3 - Prob. 29ECCh. 6.3 - Prob. 30ECCh. 6.4 - Applying the Concepts 64 Mountain Climbing Safety...Ch. 6.4 - Explain why a normal distribution can be used as...Ch. 6.4 - What conditions must be met to use the normal...Ch. 6.4 - Why is a correction for continuity necessary?Ch. 6.4 - When is the normal distribution not a good...Ch. 6.4 - Prob. 5ECh. 6.4 - Prob. 6ECh. 6.4 - Check each binomial distribution to see whether it...Ch. 6.4 - Check each binomial distribution to see whether it...Ch. 6.4 - Prob. 9ECh. 6.4 - School Enrollment Of all 3- to 5-year-old...Ch. 6.4 - Home Ownership In a recent year, the rate of U.S....Ch. 6.4 - Mail Order A mail order company has an 8% success...Ch. 6.4 - Prob. 13ECh. 6.4 - Prob. 14ECh. 6.4 - Prob. 15ECh. 6.4 - Population of College Cities College students...Ch. 6.4 - Prob. 17ECh. 6.4 - Prob. 18ECh. 6.4 - Female Americans Who Have Completed 4 Years of...Ch. 6.4 - Prob. 20ECh. 6.4 - Elementary School Teachers Women comprise 80.3% of...Ch. 6.4 - Prob. 22ECh. 6.4 - Prob. 23ECCh. 6 - Prob. 6.1.1RECh. 6 - Find the area under the standard normal...Ch. 6 - Prob. 6.1.3RECh. 6 - Using the standard normal distribution, find each...Ch. 6 - Per Capita Spending on Health Care The average per...Ch. 6 - Prob. 6.2.6RECh. 6 - Commuter Train Passengers On a certain run of a...Ch. 6 - Monthly Spending for Paging and Messaging Services...Ch. 6 - Cost of Smartphone Repair The average cost of...Ch. 6 - Prob. 6.2.10RECh. 6 - Private Four-Year College Enrollment A random...Ch. 6 - Heights of Active Volcanoes The heights (in feet...Ch. 6 - Confectionary Products Americans ate an average of...Ch. 6 - Average Precipitation For the first 7 months of...Ch. 6 - Sodium in Frozen Food The average number of...Ch. 6 - Prob. 6.3.16RECh. 6 - Retirement Income Of the total population of...Ch. 6 - Slot Machines The probability of winning on a slot...Ch. 6 - Multiple-Job Holders According to the government,...Ch. 6 - Enrollment in Personal Finance Course In a large...Ch. 6 - Prob. 6.4.21RECh. 6 - Larceny-Thefts Excluding motor vehicle thefts, 26%...Ch. 6 - Determine whether each statement is true or false....Ch. 6 - Prob. 2CQCh. 6 - Determine whether each statement is true or false....Ch. 6 - The z value corresponding to a number below the...Ch. 6 - Determine whether each statement is true or false....Ch. 6 - Prob. 6CQCh. 6 - Select the best answer. 7. The mean of the...Ch. 6 - Approximately what percentage of normally...Ch. 6 - Which is not a property of the standard normal...Ch. 6 - When a distribution is positively skewed, the...Ch. 6 - Prob. 11CQCh. 6 - Complete the following statements with the best...Ch. 6 - The difference between a sample mean and a...Ch. 6 - The mean of the sample means equals ________.Ch. 6 - The standard deviation of all possible sample...Ch. 6 - The normal distribution can be used to approximate...Ch. 6 - Prob. 17CQCh. 6 - Find the area under the standard normal...Ch. 6 - Using the standard normal distribution, find each...Ch. 6 - Amount of Rain in a City The average amount of...Ch. 6 - Heights of People The average height of a certain...Ch. 6 - Sports Drink Consumption The average number of...Ch. 6 - Years to Complete a Graduate Program The average...Ch. 6 - Passengers on a Bus On the daily run of an express...Ch. 6 - Thickness of Library Books The average thickness...Ch. 6 - Prob. 26CQCh. 6 - Prob. 27CQCh. 6 - Electric Bills The average electric bill in a...Ch. 6 - Sleep Survey According to a recent survey, 38% of...Ch. 6 - Prob. 30CQCh. 6 - Household Online Connection The percentage of U.S....Ch. 6 - Prob. 32CQCh. 6 - Prob. 33CQCh. 6 - GMAT Scores The average GMAT scores for the top-30...Ch. 6 - Prob. 1CTCCh. 6 - Sometimes a researcher must decide whether a...Ch. 6 - Prob. 3CTCCh. 6 - Prob. 4CTCCh. 6 - Sometimes a researcher must decide whether a...Ch. 6 - Prob. 6CTCCh. 6 - Prob. 7CTCCh. 6 - Prob. 8CTCCh. 6 - Formulas Confirm the two formulas hold true for...
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