3rd Edition

ISBN: 9780135190210

Author: Gould

Publisher: PEARSON CO

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A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.

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Textbook Question

Chapter 9, Problem 30SE

Travel Time to School A random sample of 50 12th-grade students was asked how long it took to get to school. The sample mean was 16.2 minutes, and the sample standard deviation was 12.3 minutes. (Source: AMSTAT Census at School)

a. Find a 95 % confidence interval for the population mean time it takes 12th-grade students to get to school.

b. Would a 90 % confidence interval based on this sample data be wider or narrower than the 95 % confidence interval? Explain. Check your answer by constructing a 90 % confidence interval and comparing this width of the interval with the width of the 95 % confidence interval you found in part a.

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Chapter 9, Problem 29SE

Chapter 9, Problem 31SE

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Chapter 9 Solutions

EP INTRODUCTORY STATISTICS-MYSTATLAB

Ch. 9 - Ages A study of all the students at a small...Ch. 9 - Units A survey of 100 random full-time students at...Ch. 9 - Exam Scores The distribution of the scores on a...Ch. 9 - Exam Scores The distribution of the scores on a...Ch. 9 - Showers According to home-water-works.org, the...Ch. 9 - Smartphones According to a 2017 report by ComScore...Ch. 9 - Retirement Income Several times during the year,...Ch. 9 - Time Employed A human resources manager for a...Ch. 9 - Driving (Example 1) Drivers in Wyoming drive more...Ch. 9 - Driving Drivers in Alaska drive fewer miles yearly...

Ch. 9 - Babies Weights (Example 2) Some sources report...Ch. 9 - Babies’ Weights, Again Some sources report that...Ch. 9 - (Example 3) Income in Maryland According to a 2018...Ch. 9 - Income in Kansas According to a 2018 Money...Ch. 9 - CLT Shapes (Example 4) One of the histograms is a...Ch. 9 - Used Van Costs One histogram shows the...Ch. 9 - (Example 5) Age of Used Vans The mean age of all...Ch. 9 - Student Ages The mean age of all 2550 students at...Ch. 9 - Prob. 19SE Ch. 9 - Prob. 20SE Ch. 9 - Prob. 21SE Ch. 9 - Prob. 22SE Ch. 9 - Private University Tuition (Example 7) A random...Ch. 9 - Random Numbers If you take samples of 40 lines...Ch. 9 - t* (Example 8) A researcher collects one sample of...Ch. 9 - t* A researcher collects a sample of 25...Ch. 9 - Heights of 12th Graders (Example 9) A random...Ch. 9 - Drinks A fast-food chain sells drinks that it...Ch. 9 - Men’s Pulse Rates (Example 10) A random sample of...Ch. 9 - Travel Time to School A random sample of 50...Ch. 9 - RBIs (Example 11) A random sample of 25 baseball...Ch. 9 - RBIs Again In exercise 9.31, two intervals were...Ch. 9 - Confidence Interval Changes State whether each of...Ch. 9 - Confidence Interval Changes State whether each of...Ch. 9 - Potatoes The weights of four randomly and...Ch. 9 - Tomatoes The weights of four randomly and...Ch. 9 - Human Body Temperatures (Example 12) A random...Ch. 9 - Reaction Distance Data on the disk and website...Ch. 9 - Potatoes Use the data from exercise 9.35. a. If...Ch. 9 - Tomatoes Use the data from exercise 9.36. a. Using...Ch. 9 - Cholesterol In the U.S. Department of Health has...Ch. 9 - BMI A body mass index (BMI) of more than 25 is...Ch. 9 - Male Height In the United States, the population...Ch. 9 - Female Height In the United States, the population...Ch. 9 - Deflated Footballs? Patriots In the 2015 AFC...Ch. 9 - Deflated Footballs? Colts In the 2015 AFC...Ch. 9 - Movie Ticket Prices According to Deadline.com, the...Ch. 9 - Broadway Ticket Prices According to Statista.com,...Ch. 9 - Atkins Diet Difference Ten people went on an...Ch. 9 - Pulse Difference The following numbers are the...Ch. 9 - Student Ages Suppose that 200 statistics students...Ch. 9 - Presidents’ Ages at Inauguration A 95 confidence...Ch. 9 - Independent or Paired (Example 13) State whether...Ch. 9 - Independent or Paired State whether each situation...Ch. 9 - Televisions: CI (Example 14) Minitab output is...Ch. 9 - Pulse and Gender: CI Using data from NHANES, we...Ch. 9 - Televisions (Example 15) The table shows the...Ch. 9 - Pulse Rates Using data from NHANES, we looked at...Ch. 9 - Triglycerides Triglycerides are a form of fat...Ch. 9 - Systolic Blood Pressures When you have your blood...Ch. 9 - Triglycerides, Again Report and interpret the 95...Ch. 9 - Blood Pressures, Again Report and interpret the 95...Ch. 9 - Baseball Salaries A random sample of 40...Ch. 9 - College Athletes’ Weights A random sample of male...Ch. 9 - Baseball Salaries In exercise 9.63 you could not...Ch. 9 - College Athletes’ Weights In exercise 9.64, you...Ch. 9 - Textbook Prices, UCSB vs. CSUN (Example 16) The...Ch. 9 - Textbook Prices. OC vs. CSUN The prices of a...Ch. 9 - Females’ Pulse Rates before and after a Fright...Ch. 9 - Males’ Pulse Rates before and after a Fright...Ch. 9 - Organic Food A student compared organic food...Ch. 9 - Body Temperature The body temperatures of 65 men...Ch. 9 - Ales vs. IPAs Data were collected on calorie...Ch. 9 - Surfers Surfers and statistics students Rex...Ch. 9 - Self-Reported Heights of Men (Example 18) A random...Ch. 9 - Eating Out Jacqueline Loya, a statistics student,...Ch. 9 - Prob. 77SE Ch. 9 - Self-Driving Cars A survey of asked respondents...Ch. 9 - Women’s Heights Assume women’s heights are...Ch. 9 - Showers According to home-water-works.org, the...Ch. 9 - Choose a test for each situation: one-sample...Ch. 9 - Choose a t-test for each situation: one-sample...Ch. 9 - Cones: 3 Tests A McDonald’s fact sheet says its...Ch. 9 - Prob. 84CRE Ch. 9 - Brain Size Brain size for 20 random women and 20...Ch. 9 - Reducing Pollution A random sample of 12th-grade...Ch. 9 - Heart Rate before and after Coffee Elena Lucin, a...Ch. 9 - Exam Grades The final exam grades for a sample of...Ch. 9 - Hours of Television Viewing The number of hours...Ch. 9 - Reaction Distances Reaction distances in...Ch. 9 - Ales vs. Lagers Data were collected on calorie...Ch. 9 - Weights of Hockey and Baseball Players Data were...Ch. 9 - Grocery Delivery The table shows the prices for...Ch. 9 - Parents The following table shows the heights (in...Ch. 9 - Why Is n1 in the Sample Standard Deviation? Why do...Ch. 9 - Prob. 96CRE Ch. 9 - Construct two sets of body temperatures (in...Ch. 9 - Construct heights for 3 or more sets of twins (6...

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Solution Summary: The author calculates the 95% confidence interval for the population mean for 12th-grade students to reach school, using the MINITAB software.

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Chapter 9 Solutions