
Concept explainers
a.
Check whether who takes out the trash is random.
a.

Answer to Problem 1E
Yes, the person who takes out the trash is random.
Explanation of Solution
A coin is flipped to decide who takes out the trash.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular outcome is not possible, then that particular outcome is said to be random.
Here, the experimenter flips a coin to decide who takes out the trash. It is not possible to predict the outcome of a coin when it is tossed. It might be either head or tail.
The experimenter flips a coin and selects a person based on the outcome of the coin. Here, the investigator might select a person if the tossed coin shows head or select a person if the tossed coin shows tail. The outcome of the tossed coin (Either head or tail) is purely random. Thus, a person is randomlyselected to decide the person who takes out the trash according to the outcome.
Hence, the experimenter implements the randomization by randomly assigninga person to take out the trash.
Thus, the person who takes out the trash is random.
b.
Check whether the sports team named by the friend is random.
b.

Answer to Problem 1E
No, the sports team named by the friend is not random.
Explanation of Solution
A sports team is named by asking a friend to quickly name a professional sports team.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular is outcome is not possible, then that particular outcome is said to be random.
Here, the sports team is named by asking a friend to quickly name a professional sports team.
The experimenter selects a sports team by asking a friend to quickly name a professional sports team.
Since, a friend knows likes and dislikes of his friendand he might guess the name of the sports team which his friend is about to give. Therefore, the spots team named by friend is predictable. Thus, a sports team named by the friend is not randomly selected.
Hence, the experimenter does not implement randomization.
Thus, the sports team named by friendis not named at random.
c.
Check whether the roommate for the year is random.
c.

Answer to Problem 1E
Yes, the roommate for the year is random.
Explanation of Solution
Names are selected out of a hat to decide roommates in a dormitory.
Randomization:
The process of allocating experimental units to the treatments in an experiment using probability is known as randomization.
Randomization minimizes the difference between groups by equally distributing the individuals. By randomization, individuals are assigned to corresponding treatment randomly. Randomization reduces the observer bias, the effect of the order in which the treatments are administered and accounts for the uncontrolled factors in the experiment. Randomization helps to eliminate or reduce the effects of the factors, which cannot be controlled in the experiment.
When the exact prediction of a particular is outcome is not possible, then that particular outcome is said to be random.
Here, the experimenter selected the roommates in a dormitory by selecting names out of a hat.
The experimenter selects a name out of a hat and decides the roommate based on the outcome of the hat. The names of the roommates in a dormitory which are about to pick by the experimenter is not predictable. Thus, name of roommates in a dormitory is randomly selected by the experimenter.
Hence, the experimenter implements the randomization by randomly selecting the roommate name.
Thus, the roommate for the year is random.
Want to see more full solutions like this?
Chapter 10 Solutions
STATS:DATA+MODELS-W/DVD
- 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?arrow_forwardA 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_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 127arrow_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 8 136 127 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_forward
- If 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_forwardProblem 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_forward
- Solve 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_forwardged 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_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics 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:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman





