In: Statistics and Probability
Please explain how to do 1a and b throughly, thank you!
1A) A psychologist specializing in marriage counseling claims that, among all married couples, the proportion p for whom her communication program can prevent divorce is at least 76%. In a random sample of 225 married couples who completed her program, 164 of them stayed together. Based on this sample, can we reject the psychologist's claim at the 0.01 level of significance?Perform a one-tailed test. Then fill in the table below.
Carry your intermediate computations to at least three decimal places and round your answers as specified in the table.
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1B) Citrus Rental is a popular car rental agency that has a history of having too few cars available, so that its available cars are overdriven. The mean monthly mileage over the years for Citrus cars has been about 1600 miles per month. Recently, though, Citrus purchased thousands of new cars, and the company claims that the average mileage of its cars is now less than in the past. To test this, a random sample of 12 recent mileages of Citrus cars was taken. The mean of these 12 mileages was 1565 miles per month, and the standard deviation was 210 miles per month. Assume that the population of recent monthly mileages of Citrus cars is normally distributed. At the 0.1 level of significance, can it be concluded that the mean recent monthly mileage, μ, of Citrus cars is less than 1600 miles per month?
Perform a one-tailed test. Then fill in the table below.
Carry your intermediate computations to at least three decimal places and round your answers as specified in the table.
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