Workout the following problems and show all necessary steps. Use Algebra. In a random sample of 40 refrigerators, the mean repair cost was $150. Assume the population standard deviation = $15.5.  a. Construct a 99% interval for the population mean repair cost. Interpret the results. b. Repeat exercise 1a, changing the sample size to n=60. Which confidence interval has a better estimate? Why? Explain? c. Repeat exercise 1a, using a population standard deviation of $19.5. Which confidence interval is wider? Explain.

Q: Dalton is a public school teacher in Burlington. After a conversation with a colleague in Sudbury,…

A: Explanation:Denote µ1 = true population mean for Burlington teachers’ salary and µ2 = true…

Q: Use the following setup to answer the following questions. Draw a diagram where asked. A real estate…

A: For the given data Perform t test for one mean

Q: Researchers collected information on the body parts of a new species of frog. The thumb length for…

A: The mean is 6.74 and the standard deviation is 0.67.

Q: One-Sample Statistics Std. Deviation Std. Error Mean Mean hrs1 NUMBER OF HOURS WORKED LAST WEEK 895…

A: From the given output, it is clear that t test had been done. 1. The test done was One sample t test…

Q: Russell is doing some research before buying his first house. He is looking at two different areas…

A: Formula : CI=(x̄1 - x̄2) ± ME

Q: 1 2 13 r= 4 5 9 3 8 6 5 Calculate the sample correlation coefficient (r) to three decimal places.…

A:

Q: Use the sample mean(78.5)and sample standard deviation (12.3671)in your calculations below. Use…

A: Given that:

Q: Choose a quantitative variable.  Measure it on two different samples of 10, drawn from two different…

A:

Q: McDonald’s advertises that its ice cream cones have a mean weight of 3.2 ounces.  A human server…

A:

Q: Given a mean of 24.5 and a standard deviation of 1.7, within how many standard deviations of the…

A: A mean of 24.5 and a standard deviation of 1.7

Q: Russell is doing some research before buying his first house. He is looking at two different areas…

A:

Q: A successful basketball player has a height of 6 feet 8 ​inches, or 203 cm. Based on statistics from…

A: Consider X is a random variable defined as the height of a successful basketball player.The provided…

Q: A market researcher wants to estimate the amount of money that a Christmas shopper will spend on…

A: We have to find sample size for given data..

Q: 2. construct a 95% confidence interval for the population mean. Assume the population has a normal…

A: given data sample size (n) = 20sample mean ( x¯ ) = 3120sample standard deviation (s) =67795% ci for…

Q: Tom scored a 117 on a measure of math ability and a 41 on a measure of verbal ability. The means and…

A:

Q: With your sample of 25 inmates, you want to test if the population mean age is different from 40 at…

A: for more information ping me    happy learning

Q: Given that a data set has the following data values: 2, 4, 6, what would be the standard deviation?…

A: We have given that,  The data set are : 2, 4, 6 Then,  We will find the standard deviation (s) = ?

Q: In order to set rates, an insurance company is trying to estimate the number of sick days that full…

A: Standard deviation,  = 2.8​​​​​​True mean differs from the sample mean by one more than one day…

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: Find the p-value. (Type an integer or decimal rounded to three decimal places as needed.)

A: The test statistic is, t=x¯-μsn=37.9-38215=-0.1936≈-0.19 The test statistic is -0.19. The degrees of…

Q: ACT Scores A survey of 1000 students nationwide showed a mean ACT score of 21.4. A survey of 500…

A:

Q: You work for a consumer advocate agency and want to estimate the population mean cost of replacing a…

A: According to bartleby expert guidelines we can answer only first three subparts. Rest can be repost.

Q: A tire company finds the lifespan for one brand of its tires is normally distributed with a mea…

A: Z is known as standard normal variable and it's value is obtained using standard Normal table.

Q: A local health clinic surveys 50 patients about their water drinking habits. It found the data is…

A: n=50 Mean=62 Standard deviation=5.2 Confidence level=95%

Q: Salaries for teachers in a particular elementary school district are normally distributed with a…

A: It is given that the mean is 47,000 and standard deviation is 4,600.

Q: Mr. Stant collected information on how much customers spend at Walmart and Target. He created the…

A: The histogram for Walmart is symmetrical and bimodal but the high frequencies are observed at…

Q: You are applying for a job at two companies. Company A offers starting salaries with p = $33,000 and…

A: The mean and standard deviation for Company A are 33,000 and 1,000. The mean and standard deviation…