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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?

The amount of calories in a small serving of French Fries at McDonalds is Normally distributed with a mean of 230 calories and a standard deviation of 25. Suppose that a random sample of 15 small servings was collected. What is the probability that the sample mean is greater than 240 calories?

Suppose that you took a random sample of 15 students at UF and asked them how many minutes they exercised yesterday. Suppose that you wanted to make a 90% confidence interval for the population mean. What value would you use for t?

Fifteen females were recorded on their reaction time to a stimulus. The 95% confidence interval for the population mean was (14.56, 18.75) seconds. What do we know from this confidence interval?