Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Textbook Question
Chapter 9, Problem 80SE
9.77, 9.79, and 9.80 For these questions, the data set is given at this text's website. Assume that the data sets are from random samples and the distributions are Normal.
a. Find a
b. Perform a hypothesis test to see whether the means are significantly different using a significance level of 0.05. Explain your conclusion clearly.
Shoes Compare the number pair of shoes for men and women.
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Chapter 9 Solutions
Introductory Statistics (2nd Edition)
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 - Prob. 5SECh. 9 - Cellphone Calls Answers.com claims that the mean...Ch. 9 - Retirement Income Several times during the year,...Ch. 9 - Time Employed A human resources manager for a...Ch. 9 - Prob. 9SECh. 9 - Prob. 10SE
Ch. 9 - Babies Weights (Example 2) Some sources report...Ch. 9 - Babies’ Weights, Again Some sources report that...Ch. 9 - Prob. 13SECh. 9 - Prob. 14SECh. 9 - CLT Shapes (Example 4) One of the histograms is a...Ch. 9 - Prob. 16SECh. 9 - Prob. 17SECh. 9 - Student Ages The mean age of all 2550 students at...Ch. 9 - Prob. 19SECh. 9 - Prob. 20SECh. 9 - Prob. 21SECh. 9 - Prob. 22SECh. 9 - Prob. 23SECh. 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 - Hamburgers (Example 9) A hamburger chain sells...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 - Prob. 30SECh. 9 - Prob. 31SECh. 9 - Prob. 32SECh. 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 - Vegetarians' Weights The mean weight of all...Ch. 9 - GPAs Thirty GPAs from a randomly selected sample...Ch. 9 - Prob. 46SECh. 9 - GPAs Using the data from Exercise 9.45 on GPAs,...Ch. 9 - Prob. 48SECh. 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 - Prob. 53SECh. 9 - Prob. 54SECh. 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 - Clothes Spending A random sample of 14 college...Ch. 9 - College Athletes’ Weights A random sample of male...Ch. 9 - Prob. 65SECh. 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 - Smoking Mothers The birth weights of 35 babies...Ch. 9 - Ages of Brides and Grooms Data for the ages of...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 - 9.77, 9.79, and 9.80 For these questions, the data...Ch. 9 - Prob. 78SECh. 9 - 9.77, 9.79, and 9.80 For these questions, the data...Ch. 9 - 9.77, 9.79, and 9.80 For these questions, the data...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. 84CRECh. 9 - Brain Size Brain size for 20 random women and 20...Ch. 9 - Prob. 86CRECh. 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 - Shift Sleep Hours A survey was done comparing the...Ch. 9 - Prob. 92CRECh. 9 - Maximum Tax Rate A random sample of 10 Democrats...Ch. 9 - Prob. 94CRECh. 9 - Groceries The table shows the prices of identical...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. 98CRECh. 9 - Construct two sets of body temperatures (in...Ch. 9 - Construct heights for 3 or more sets of twins (6...
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