20. Exam Completion Time The mean time it tåkes 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: 29. The standard deviation of a variable is 15. If a sample of 100 individuals is selected, what…

A: Since you have posted more than one question, we are answering the first question as per our rule.…

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

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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: Suppose a population is unimodal and symmetric with mean 55 and standard deviation 7.  a.…

A: Consider X be a random which follows normal distribution with a mean of 55 and standard deviation of…

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: (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…

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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…

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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…

Statements and Logic

Logic is the analysis of general patterns of thoughts without regard to any specific sense of context.