20. Exam Completion Time The mean time it takes a group of students to complete a statistics final exam is 44 minutes, and the standard deviation is 9 minutes. Within what limits would you expect approximately 95% of the students to complete the exam? Assume the variable is approximately normally distributed.

Q: 2. Suppose that the people living in a particular city were found to have a mean score of 40 and a…

A: People living in particular city were found to have a mean score of 40 and standard deviation as 5,…

Q: The distribution of passenger vehicle speeds traveling on the Interstate 5 Freeway (I-5) in…

A: Note: Hi, thank you for the question. As per our company guideline we are supposed to answer only…

Q: 4.18  stats for the social sciences. According to a recent Current Population Reports, self-employed…

A: GivenThe average time self employed individuals in United States work = 45 hours per weekThe…

Q: 1. A psychology exam has 300 questions with each question worth 1 point. Assume that the…

A: Given information: Let X be the grades in a psychology exam. Then X is a random variable from Normal…

Q: In the 2004 election in Utah, 66% of all Utah voters voted for Amendment 3, the marriage amendment.…

A: The formula to compute the standard deviation of the sampling distribution of p̂ is written as:…

Q: 6. The annual salaries of employees in a large company are approximately normally distributed with a…

A: Given: Mean, μ = 50000       Standard deviation, σ=20000      Let X denote the 85th percentile…

Q: 20. The exam scores of 300 students are distributed normally with a mean of 72 and a standard…

A: 20). The provided information is: Sample sizen=300 Meanμ=72 Standard deviationσ=10 Assume that X is…

Q: 11. Chebyshev's Theorem states that the percentage of measurements in a data set that fall within…

A:

Q: Suppose weights of newborn babies in one community are normally distributed with a mean of 7.5…

A: Given weights of newborn babies in one community are normally distributed with a mean             =…

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: Given, n1 = 20          n2=21x1=211          x2=222σ12=20            σ22=25 Level of significance =…

Q: 4-The grade distribution of a recent exam follows a normal distribution with the following summary:…

A: In a normal disrtibution,

Q: 18. The time it takes for Grade 11 students in a certain school to complete a physical fitness test…

A: Normal distribution is a continuous distribution that has many real-life applications. The standard…

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: Introduction: Denote μ1, μ2 as the true mean repair costs for washing machines of Model A and Model…

Q: 9. The mean July daily rainfall in Waterville is 10 mm and the standard deviation is 1.5 mm. Assume…

A: Consider a random variable X which represent that amount of daily rainfall in Waterville in the…

Q: ngineers must consider the breadths of male heads when designing helmets. The company researchers…

A:

Q: (ii) The distribution of heights of students in a large class is roughly bell-shaped. The average…

A: In this context, the average height is 68 inches. Approximately 95% of the heights are 62 and 74…

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: Introduction: Denote μ1, μ2 as the true mean repair costs for washing machines of Model A and Model…

Q: The Economic Policy Institute periodically issues reports on workers' wages. Suppose the institute…

A: We have to use normal distribution approximation to find out the probabilities.

Q: Emergency Room Traffic. Desert Samaritan Hospital in Mesa, Arizona, keeps records of emergency room…

A: GivenThe times between arriving patients have mean of 8.7 minutes and standard deviation of 8.7…

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A:

Q: For data that is normally distributed, is it possible for the standard deviation to be larger than…

A:

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A:

Q: 6. If a one-person household spends an average of $40 per week on groceries, find the maximum and…

A:

Q: Engineers must consider the breadths of male heads when designing helmets. The company researchers…

A: Let X be the breadths of male heads while designing helmets. The distribution is normally…

Q: a used car lot lowers the price of every car in the lot by $300. what effect, if any will this have…

A: Mean, median and mode will decrease by $300.

Q: A population is normally distributed with a mean of 25 and a standard deviation of 3. What is the z…

A: GIVEN DATA,μ=25σ=3X=18z=?

Q: 1. A survey found that the American family generates an average of 17.2 pounds of glass garbage each…

A: Given Population mean μ=17.2, population standard deviations σ=2.5, n=55  Note: This probability…

Q: 22. A six-year study in a certain country found that birth weights of newborns were normally…

A: Let, X: The weight of a newborn in grams. Given: Mean = μ= 3758 Standard deviation = σ = 496 And X…

Q: Your dorm mate tells you that blue ring octopus venom, administered at the correct dosage, can…

A:

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: From the provided information,

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: Here, the population standard deviation is known. Hence, it is appropriate to use normal…

Q: 2. The average number of customers that visited a particular store during the past year is 160 per…

A:

Q: A population has a mean of 90 and a standard deviation of 7. If it is sampled repeatedly with…

A: Given that  Mean=mu=90  Standard deviation=sigma=7 n=169

Q: 3. The amount of beer Finnish people drink per year is normally distributed with 1 = 78.7 liters and…

A: We have to find correct answer for given data..

Q: You want to buy a washing machine, and a salesperson tells you that the mean repair costs for Model…

A: Given, -x1 = 211, -x2 = 222 σ1 = 20, σ2 = 25 n1 = 20, n2 = 21 α = 0.01

Q: 29. The standard deviation of a variable is 15. If a sample of 100 individuals is selected, what…

A: The complete solutions are given below

Q: can you reject the​ salesperson's claim?

A: Given,  samples are random and independent and populations are normally distributed.…

Q: . The distribution of passenger vehicle speeds traveling on the Interstate 5 Freeway (I-5) in…

A: Given that  The distribution of passenger vehicle speeds traveling on the Interstate 5 Freeway (I-5)…

Q: The heights of a pediatricians three-year-old females are approximately normally distributed, with…

A: Solution: Let X be the height of a pediatricians three-year-old females. From the given information,…

Q: 3. Several intelligence tests follow a normal distribution with a mean of 100 and a standard…

A: Let X represent the random variable   X~ Normal (100, 15^2)

Q: 20. Twenty percent of the students in a class of 100 are planning to go to graduate school. The…

A:

Q: 3. A data set is normally distributed with a mean of 50 and a standard deviation of 8. What percent…

A:

Q: . Scientists estimate that the distribution of the life span of the Galápagos Islands giant…

A: We have given that Mean(µ) = 100Standard deviations (σ) = 15X ~ N (µ, σ )= N(100, 15)

Q: A population has a mean of 90 and a standard deviation of 7. If it is sampled repeatedly with…

A: Given Mean=90 Standard deviations=7

Q: 6. a lower value of the standard deviation for a data set indicates that the values of that data set…

A: 6)  The given statement is

Q: The college students’ GPA's are normally distributed with a mean of 2.9 and standard deviation of…

A: Given : mean = 2.9 Standard deviation = 0.6

Q: For a normal distribution with a mean of 160 and a standard deviation of 10, what are the values…

A: Solution

Q: The mean and standard deviation of a population are 200 and 20, respectively. The probability of…

A: Since you have asked multiple question, we will solve the first question for you. If you want any…

Estimation

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.