In a random and independent sample of 1000 students 80% of them were in favor of longer hours at the school library. What is the margin or error (MOE) for the 95% confidence interval level?

In a study of speed dating, male subjects were asked to rate the attractiveness of their female dates, and a sample of the results is listed below (1 = not attractive; 10 = extremely attractive). Construct a confidence interval using a 90% confidence level. What do the results tell about the mean attractiveness ratings of the population of all adult females?7,7,1,8,6,5,8,8,8,8,5,9 What is the confidence interval for the population mean u?  __<u<__ (Round to one decimal place as needed.)

A study is conducted by a physical therapist to determine whether there is a difference in the proportion of men and women in the U.S. that participate in regular sustained physical activity. It is found that 22% of menout of 550 and 19.5% of women out of 450 participated in regular sustained physical activity. Construct a 90% confidence interval for the difference in proportions of men and women that participate in regular sustained and state your conclusion.

Suppose you are planning an experiment and a sample has yet been selected. For this experiment you plan on taking a SRS of 50 mice with pancreatic cancer measuring a particular hormone level. What would be the impact on a 95% confidence interval calculated from the experiment on these mice if instead of a SRS of 50 mice, a SRS of 200 mice were taken?

A recent poll indicated that 42% of men supported raises taxes to fund additional park services.   The poll also found that 64% of women supported such a tax.  The sample consisted of 29 men and 25 women.   Construct a 90% confidence interval around the difference in proportions.

In a study of treatments for very painful​ "cluster" headaches,... Find the 90% confidence interval using technology.

Several years​ ago, 45​% of parents who had children in grades​ K-12 were satisfied with the quality of education the students receive. A recent poll asked 1,025 parents who have children in grades​ K-12 if they were satisfied with the quality of education the students receive. Of the 1,025 ​surveyed, 484 indicated that they were satisfied. Construct a 99​% confidence interval to assess whether this represents evidence that​ parents' attitudes toward the quality of education have changed.

ESPN believed that 30 percent of Sportszone visitors were females. To test this hypothesis, it collected audience profile data at the ESPN SportsZone Web site and found that 36% of the visitors were females. Assume that this sample value was based on a sample of 300 users. Test its hypothesis using 95% confidence level.