Essential Statistics
2nd Edition
ISBN: 9781259570643
Author: Navidi
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Question
Chapter 7.2, Problem 6CYU
a.
To determine
Find the degrees of freedom.
b.
To determine
Find the critical value
c.
To determine
Construct a 99% confidence interval for the population mean using the critical value and the information in the display.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Calculate the 90% confidence interval for the population mean difference using the data in the attached image. I need to see where I went wrong.
Microsoft Excel snapshot for random sampling: Also note the formula used for the last
column
02
x✓ fx =INDEX(5852:58551, RANK(C2, $C$2:$C$51))
A
B
1
No.
States
2
1
ALABAMA
Rand No.
0.925957526
3
2
ALASKA
0.372999976
4
3
ARIZONA
0.941323044
5
4 ARKANSAS
0.071266381
Random Sample
CALIFORNIA
NORTH CAROLINA
ARKANSAS
WASHINGTON
G7
Microsoft Excel snapshot for systematic sampling:
xfx INDEX(SD52:50551, F7)
A
B
E
F
G
1
No.
States
Rand No. Random Sample
population
50
2
1 ALABAMA
0.5296685 NEW HAMPSHIRE
sample
10
3
2 ALASKA
0.4493186 OKLAHOMA
k
5
4
3 ARIZONA
0.707914 KANSAS
5
4 ARKANSAS 0.4831379 NORTH DAKOTA
6
5 CALIFORNIA 0.7277162 INDIANA
Random Sample
Sample Name
7
6 COLORADO 0.5865002 MISSISSIPPI
8
7:ONNECTICU 0.7640596 ILLINOIS
9
8 DELAWARE 0.5783029 MISSOURI
525
10
15
INDIANA
MARYLAND
COLORADO
Suppose the Internal Revenue Service reported that the mean tax refund for the year 2022 was $3401. Assume the standard deviation is $82.5 and that the amounts refunded follow a normal probability distribution. Solve the following three parts? (For the answer to question 14, 15, and 16, start with making a bell curve. Identify on the bell curve where is mean, X, and area(s) to be determined.
1.What percent of the refunds are more than $3,500?
2. What percent of the refunds are more than $3500 but less than $3579?
3. What percent of the refunds are more than $3325 but less than $3579?
Chapter 7 Solutions
Essential Statistics
Ch. 7.1 - Prob. 1CYUCh. 7.1 - Prob. 2CYUCh. 7.1 - Prob. 3CYUCh. 7.1 - Prob. 4CYUCh. 7.1 - Prob. 5CYUCh. 7.1 - Prob. 6CYUCh. 7.1 - Prob. 7CYUCh. 7.1 - Prob. 8CYUCh. 7.1 - Prob. 9CYUCh. 7.1 - 10. Using the output in Exercise 9:
Find the...
Ch. 7.1 - Prob. 11CYUCh. 7.1 - 12. The researchers now plan to construct a 99%...Ch. 7.1 - Prob. 13CYUCh. 7.1 - 14. An IQ test is designed to have scores that...Ch. 7.1 - Prob. 15CYUCh. 7.1 - Prob. 16CYUCh. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - Prob. 19ECh. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - In Exercises 21–24, determine whether the...Ch. 7.1 - Prob. 22ECh. 7.1 - Prob. 23ECh. 7.1 - Prob. 24ECh. 7.1 - Prob. 25ECh. 7.1 - In Exercises 25–28, find the critical value zα∕2...Ch. 7.1 - Prob. 27ECh. 7.1 - Prob. 28ECh. 7.1 - Prob. 29ECh. 7.1 - In Exercises 29–32, find the levels of the...Ch. 7.1 - Prob. 31ECh. 7.1 - Prob. 32ECh. 7.1 - Prob. 33ECh. 7.1 - Prob. 34ECh. 7.1 - Prob. 35ECh. 7.1 - 36. A sample of size n = 64 is drawn from a...Ch. 7.1 - 37. A sample of size n = 10 is drawn from a normal...Ch. 7.1 - 38. A sample of size n = 80 is drawn from a normal...Ch. 7.1 - Prob. 39ECh. 7.1 - Prob. 40ECh. 7.1 - Prob. 41ECh. 7.1 - Prob. 42ECh. 7.1 - 43. SAT scores: A college admissions officer takes...Ch. 7.1 - Prob. 44ECh. 7.1 - Prob. 45ECh. 7.1 - Prob. 46ECh. 7.1 - Prob. 47ECh. 7.1 - Prob. 48ECh. 7.1 - Prob. 49ECh. 7.1 - Prob. 50ECh. 7.1 - Prob. 51ECh. 7.1 - Prob. 52ECh. 7.1 - Prob. 53ECh. 7.1 - Prob. 54ECh. 7.1 - Prob. 55ECh. 7.1 - 56. Different standard deviations: Martin and...Ch. 7.1 - Prob. 57ECh. 7.1 - Prob. 58ECh. 7.1 - Prob. 59ECh. 7.1 - Prob. 60ECh. 7.1 - Prob. 61ECh. 7.1 - Prob. 62ECh. 7.1 - Prob. 63ECh. 7.1 - Prob. 64ECh. 7.1 - Interpret computer output: The following MINITAB...Ch. 7.1 - Interpret computer output: The following MINITAB...Ch. 7.1 - Prob. 67ECh. 7.1 - Prob. 68ECh. 7.2 - Prob. 1CYUCh. 7.2 - Prob. 2CYUCh. 7.2 - 3. A potato chip company wants to evaluate the...Ch. 7.2 - Prob. 4CYUCh. 7.2 - Prob. 5CYUCh. 7.2 - Prob. 6CYUCh. 7.2 - Prob. 7ECh. 7.2 - In Exercises 7 and 8, fill in each blank with the...Ch. 7.2 - In Exercises 9 and 10, determine whether the...Ch. 7.2 - In Exercises 9 and 10, determine whether the...Ch. 7.2 - Prob. 11ECh. 7.2 - Prob. 12ECh. 7.2 - Prob. 13ECh. 7.2 - 14. A sample of size n = 22 is drawn from a normal...Ch. 7.2 - 15. A sample of size n = 12 is drawn from a normal...Ch. 7.2 - Prob. 16ECh. 7.2 - 17. A sample of size n = 15 has sample mean and...Ch. 7.2 - Prob. 18ECh. 7.2 - Prob. 19ECh. 7.2 - Prob. 20ECh. 7.2 - Prob. 21ECh. 7.2 - Prob. 22ECh. 7.2 - 23. Fake Twitter followers: Many celebrities and...Ch. 7.2 - Prob. 24ECh. 7.2 - Prob. 25ECh. 7.2 - 26. Sound it out: Phonics is an instructional...Ch. 7.2 - Prob. 27ECh. 7.2 - Prob. 28ECh. 7.2 - Baby weights: Following are weights, in pounds, of...Ch. 7.2 - Eat your cereal: Boxes of cereal are labeled as...Ch. 7.2 - Prob. 31ECh. 7.2 - Mortgage rates: Following are interest rates...Ch. 7.2 - Prob. 33ECh. 7.2 - Big salary for the boss: Following is the total...Ch. 7.2 - Prob. 35ECh. 7.2 - Prob. 36ECh. 7.2 - Prob. 37ECh. 7.2 - Sleeping outlier: A simple random sample of eight...Ch. 7.2 - Prob. 39ECh. 7.2 - Prob. 40ECh. 7.2 - Prob. 41ECh. 7.2 - Prob. 42ECh. 7.2 - Prob. 43ECh. 7.2 - Prob. 44ECh. 7.2 - Prob. 45ECh. 7.2 - Interpret computer output: The following MINITAB...Ch. 7.2 - Prob. 47ECh. 7.3 - A simple random sample of 200 third-graders in a...Ch. 7.3 - Prob. 2CYUCh. 7.3 - A pollster is going to sample a number of voters...Ch. 7.3 - Prob. 4CYUCh. 7.3 - Prob. 5CYUCh. 7.3 - In a simple random sample of 15 seniors from a...Ch. 7.3 - Prob. 7ECh. 7.3 - Prob. 8ECh. 7.3 - Prob. 9ECh. 7.3 - Prob. 10ECh. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - Prob. 13ECh. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - In Exercises 15–18, use the given data to...Ch. 7.3 - In Exercises 15–18, use the given data to...Ch. 7.3 - Prob. 17ECh. 7.3 - Prob. 18ECh. 7.3 - Smart phone: Among 238 cell phone owners aged...Ch. 7.3 - Working at home: According to the U.S. Census...Ch. 7.3 - Sleep apnea: Sleep apnea is a disorder in which...Ch. 7.3 - Internet service: An Internet service provider...Ch. 7.3 - Volunteering: The General Social Survey recently...Ch. 7.3 - SAT scores: A college admissions officer sampled...Ch. 7.3 - WOW: In the computer game World of Warcraft, some...Ch. 7.3 - Contaminated water: In a sample of 42 water...Ch. 7.3 - Call me: A sociologist wants to construct a 95%...Ch. 7.3 - Reading proficiency: An educator wants to...Ch. 7.3 - Surgical complications: A medical researcher wants...Ch. 7.3 - Prob. 30ECh. 7.3 - Changing jobs: A sociologist sampled 200 people...Ch. 7.3 - Prob. 32ECh. 7.3 - Small sample: Eighteen concrete blocks were...Ch. 7.3 - Prob. 34ECh. 7.3 - Prob. 35ECh. 7.3 - Prob. 36ECh. 7.3 - Prob. 37ECh. 7.3 - Prob. 38ECh. 7.3 - Prob. 39ECh. 7.3 - Prob. 40ECh. 7.3 - Prob. 41ECh. 7.3 - Prob. 42ECh. 7.3 - Prob. 43ECh. 7.4 - Prob. 1CYUCh. 7.4 - Prob. 2CYUCh. 7.4 - Prob. 3CYUCh. 7.4 - In Exercises 1–4, state which type of parameter is...Ch. 7.4 - Prob. 5ECh. 7.4 - In Exercises 5–10, state which type of parameter...Ch. 7.4 - In Exercises 5–10, state which type of parameter...Ch. 7.4 - Prob. 8ECh. 7.4 - Prob. 9ECh. 7.4 - Prob. 10ECh. 7.4 - Prob. 11ECh. 7.4 - Prob. 12ECh. 7.4 - Prob. 13ECh. 7.4 - Credit card debt: In a survey of 1118 U.S. adults...Ch. 7.4 - Pneumonia: In a simple random sample of 1500...Ch. 7.4 - Prob. 16ECh. 7 - Prob. 1CQCh. 7 - Prob. 2CQCh. 7 - Prob. 3CQCh. 7 - Prob. 4CQCh. 7 - Prob. 5CQCh. 7 - Prob. 6CQCh. 7 - Prob. 7CQCh. 7 - Prob. 8CQCh. 7 - Prob. 9CQCh. 7 - Prob. 10CQCh. 7 - Prob. 11CQCh. 7 - Prob. 12CQCh. 7 - Prob. 13CQCh. 7 - Prob. 14CQCh. 7 - Prob. 15CQCh. 7 - Build more parking? A survey is to be conducted in...Ch. 7 - Drill lifetime: A sample of 50 drills had a mean...Ch. 7 - Cost of environmental restoration: In a survey of...Ch. 7 - More repairs: A sample of six records for repairs...Ch. 7 - Automobile pollution: In a random sample of 85...Ch. 7 - Contaminated water: Polychlorinated biphenyls...Ch. 7 - Defective electronics: A simple random sample of...Ch. 7 - Prob. 8RECh. 7 - High octane: Fifty measurements are taken of the...Ch. 7 - Super Bowl: A simple random sample of 140...Ch. 7 - Prob. 11RECh. 7 - Prob. 12RECh. 7 - Leaking tanks: Leakage from underground fuel tanks...Ch. 7 - Prob. 14RECh. 7 - Prob. 15RECh. 7 - Prob. 1WAICh. 7 - What factors can you think of that may affect the...Ch. 7 - Prob. 3WAICh. 7 - Prob. 4WAICh. 7 - Prob. 5WAICh. 7 - When constructing a confidence interval for μ, how...Ch. 7 - Prob. 1CSCh. 7 - Prob. 2CSCh. 7 - Prob. 3CSCh. 7 - Repeat Exercises 1 and 2 for the Year 2 data. The...Ch. 7 - Prob. 5CS
Knowledge Booster
Similar questions
- A normal distribution has a mean of 50 and a standard deviation of 4. Solve the following three parts? 1. Compute the probability of a value between 44.0 and 55.0. (The question requires finding probability value between 44 and 55. Solve it in 3 steps. In the first step, use the above formula and x = 44, calculate probability value. In the second step repeat the first step with the only difference that x=55. In the third step, subtract the answer of the first part from the answer of the second part.) 2. Compute the probability of a value greater than 55.0. Use the same formula, x=55 and subtract the answer from 1. 3. Compute the probability of a value between 52.0 and 55.0. (The question requires finding probability value between 52 and 55. Solve it in 3 steps. In the first step, use the above formula and x = 52, calculate probability value. In the second step repeat the first step with the only difference that x=55. In the third step, subtract the answer of the first part from the…arrow_forwardIf a uniform distribution is defined over the interval from 6 to 10, then answer the followings: What is the mean of this uniform distribution? Show that the probability of any value between 6 and 10 is equal to 1.0 Find the probability of a value more than 7. Find the probability of a value between 7 and 9. The closing price of Schnur Sporting Goods Inc. common stock is uniformly distributed between $20 and $30 per share. What is the probability that the stock price will be: More than $27? Less than or equal to $24? The April rainfall in Flagstaff, Arizona, follows a uniform distribution between 0.5 and 3.00 inches. What is the mean amount of rainfall for the month? What is the probability of less than an inch of rain for the month? What is the probability of exactly 1.00 inch of rain? What is the probability of more than 1.50 inches of rain for the month? The best way to solve this problem is begin by a step by step creating a chart. Clearly mark the range, identifying the…arrow_forwardClient 1 Weight before diet (pounds) Weight after diet (pounds) 128 120 2 131 123 3 140 141 4 178 170 5 121 118 6 136 136 7 118 121 8 136 127arrow_forward
- Client 1 Weight before diet (pounds) Weight after diet (pounds) 128 120 2 131 123 3 140 141 4 178 170 5 121 118 6 136 136 7 118 121 8 136 127 a) Determine the mean change in patient weight from before to after the diet (after – before). What is the 95% confidence interval of this mean difference?arrow_forwardIn order to find probability, you can use this formula in Microsoft Excel: The best way to understand and solve these problems is by first drawing a bell curve and marking key points such as x, the mean, and the areas of interest. Once marked on the bell curve, figure out what calculations are needed to find the area of interest. =NORM.DIST(x, Mean, Standard Dev., TRUE). When the question mentions “greater than” you may have to subtract your answer from 1. When the question mentions “between (two values)”, you need to do separate calculation for both values and then subtract their results to get the answer. 1. Compute the probability of a value between 44.0 and 55.0. (The question requires finding probability value between 44 and 55. Solve it in 3 steps. In the first step, use the above formula and x = 44, calculate probability value. In the second step repeat the first step with the only difference that x=55. In the third step, subtract the answer of the first part from the…arrow_forwardIf a uniform distribution is defined over the interval from 6 to 10, then answer the followings: What is the mean of this uniform distribution? Show that the probability of any value between 6 and 10 is equal to 1.0 Find the probability of a value more than 7. Find the probability of a value between 7 and 9. The closing price of Schnur Sporting Goods Inc. common stock is uniformly distributed between $20 and $30 per share. What is the probability that the stock price will be: More than $27? Less than or equal to $24? The April rainfall in Flagstaff, Arizona, follows a uniform distribution between 0.5 and 3.00 inches. What is the mean amount of rainfall for the month? What is the probability of less than an inch of rain for the month? What is the probability of exactly 1.00 inch of rain? What is the probability of more than 1.50 inches of rain for the month? The best way to solve this problem is begin by creating a chart. Clearly mark the range, identifying the lower and upper…arrow_forward
- Problem 1: The mean hourly pay of an American Airlines flight attendant is normally distributed with a mean of 40 per hour and a standard deviation of 3.00 per hour. What is the probability that the hourly pay of a randomly selected flight attendant is: Between the mean and $45 per hour? More than $45 per hour? Less than $32 per hour? Problem 2: The mean of a normal probability distribution is 400 pounds. The standard deviation is 10 pounds. What is the area between 415 pounds and the mean of 400 pounds? What is the area between the mean and 395 pounds? What is the probability of randomly selecting a value less than 395 pounds? Problem 3: In New York State, the mean salary for high school teachers in 2022 was 81,410 with a standard deviation of 9,500. Only Alaska’s mean salary was higher. Assume New York’s state salaries follow a normal distribution. What percent of New York State high school teachers earn between 70,000 and 75,000? What percent of New York State high school…arrow_forwardPls help asaparrow_forwardSolve the following LP problem using the Extreme Point Theorem: Subject to: Maximize Z-6+4y 2+y≤8 2x + y ≤10 2,y20 Solve it using the graphical method. Guidelines for preparation for the teacher's questions: Understand the basics of Linear Programming (LP) 1. Know how to formulate an LP model. 2. Be able to identify decision variables, objective functions, and constraints. Be comfortable with graphical solutions 3. Know how to plot feasible regions and find extreme points. 4. Understand how constraints affect the solution space. Understand the Extreme Point Theorem 5. Know why solutions always occur at extreme points. 6. Be able to explain how optimization changes with different constraints. Think about real-world implications 7. Consider how removing or modifying constraints affects the solution. 8. Be prepared to explain why LP problems are used in business, economics, and operations research.arrow_forward
- ged the variance for group 1) Different groups of male stalk-eyed flies were raised on different diets: a high nutrient corn diet vs. a low nutrient cotton wool diet. Investigators wanted to see if diet quality influenced eye-stalk length. They obtained the following data: d Diet Sample Mean Eye-stalk Length Variance in Eye-stalk d size, n (mm) Length (mm²) Corn (group 1) 21 2.05 0.0558 Cotton (group 2) 24 1.54 0.0812 =205-1.54-05T a) Construct a 95% confidence interval for the difference in mean eye-stalk length between the two diets (e.g., use group 1 - group 2).arrow_forwardAn article in Business Week discussed the large spread between the federal funds rate and the average credit card rate. The table below is a frequency distribution of the credit card rate charged by the top 100 issuers. Credit Card Rates Credit Card Rate Frequency 18% -23% 19 17% -17.9% 16 16% -16.9% 31 15% -15.9% 26 14% -14.9% Copy Data 8 Step 1 of 2: Calculate the average credit card rate charged by the top 100 issuers based on the frequency distribution. Round your answer to two decimal places.arrow_forwardPlease could you check my answersarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSON
The Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. Freeman
Introduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman
MATLAB: An Introduction with Applications
Statistics
ISBN:9781119256830
Author:Amos Gilat
Publisher:John Wiley & Sons Inc
Probability and Statistics for Engineering and th...
Statistics
ISBN:9781305251809
Author:Jay L. Devore
Publisher:Cengage Learning
Statistics for The Behavioral Sciences (MindTap C...
Statistics
ISBN:9781305504912
Author:Frederick J Gravetter, Larry B. Wallnau
Publisher:Cengage Learning
Elementary Statistics: Picturing the World (7th E...
Statistics
ISBN:9780134683416
Author:Ron Larson, Betsy Farber
Publisher:PEARSON
The Basic Practice of Statistics
Statistics
ISBN:9781319042578
Author:David S. Moore, William I. Notz, Michael A. Fligner
Publisher:W. H. Freeman
Introduction to the Practice of Statistics
Statistics
ISBN:9781319013387
Author:David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:W. H. Freeman