Question

1. To determine the average number of hours spent studying by college students per week, a sample of 39 students was randomly selected, and found to spend an average of 17.1 hours per week, with a standard deviation of 4.3 hours. Find the 90% confidence interval for the mean number of hours spent studying per week by all college students. What is the upper and lower bound?

2. If I asked a random student how many hours they study per week, would it be unusual if the number of hours was outside of your confidence interval? Why or why not?

3. To determine the average number of hours spent studying by college students per week, a sample of 39 students was randomly selected, and found to spend an average of 17.1 hours per week, with a standard deviation of 4.3 hours. How many students would need to be surveyed at the 90% confidence level to have a maximum margin of error of 0.2 hours?

4. To estimate the number of Omaha residents who own dogs, a survey was taken with 822 randomly selected residents. Of those 822 residents, 388 responded that they own dogs. Find the point estimate for the proportion of all Omaha residents who own dogs.

Answer 1