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The average height of men in Cameroon is 1.706 meters with a standard deviation of 0.154 m. Height is approximately normally distributed. Suppose that a sample of 35 men is selected, find the range of the central 99.7% of sample mean heights?

Suppose that you wanted to estimate the population proportion of students at UF that approved of the job that what congress was doing. You decided to take a sample, but you needed to determine what size sample to take. You were uncertain what this proportion would be. You wanted to be 95% confident and to have a margin of error of 0.035. What size sample would you need?

In the year 2015, according to salary.com, nurses in Los Angelos have an average annual salary of $85,693. The standard deviation is about 6,000 dollars. The distribution of salaries is right skewed. Suppose that a sample of 20 nurses is taken from Los Angelos. What is the approximate sampling distribution of the sample mean?  

For a confidence interval for the population mean, if you increase the confidence level, what happens to the width of the interval (everything else remains the same)?

A survey of 20 randomly selected people from Gainesville were asked if they planned on purchasing a new house in the next year. Out of 20 people, 5 said yes. Can you make a 95% confidence interval for the population proportion?

For a 99% confidence interval for the population mean, what value of t would you use? n = 17

Suppose that you wanted to conduct a survey and sample UF students. Suppose you wanted to ask them how many of them planned on getting a meal plan for the Fall semester. In previous year, the proportion of students with a meal plan has been around 0.40. Suppose you want to be 95% confident and have a margin of error of 0.05. What size sample do you need?

For a confidence interval for the population mean, if you decrease the confidence level, what happens to the width of the interval (everything else remains the same)?

Suppose that 1/6 of all Americans have blue eyes. We take a random sample of 100 and find that 20 have blue eyes. What would be the mean of the sampling distribution of the sample proportion?

Suppose that you wanted to estimate the population proportion of students at UF that approved of the job that congress was doing. You decided to take a sample, but you needed to determine what size sample to take. You were uncertain what this proportion would be. You wanted to be 95% confident and to have a margin of error of 0.045. What size sample would you need?