Aston’s Career Service wants to find out what proportion of Aston’s students work in a part-time job. A similar survey undertaken 3 years ago found that 60% of Aston students worked in a part-time job. How many students must it include in the sample if it wants to achieve a ±4% accuracy at a 95% confidence level?

Students at a certain college were asked if they have a car. After surveying 601 students, it was found that 40.3% of them have a car. The margin of error was 4% with a 95% confidence level. What does this margin of error tell you about the percentage of students at that college who have a car? We can be 95% confident that somewhere between % and % of the students at that college have a car.

The manager at Bell’s Gym wants to know the proportion of members who use the Cardio Machines. A sample of 260 members showed that 40 of them use cardio machines. Calculate a 97% confidence interval for the proportion of members who use the cardio machines.

A study was being done to estimate the proportion of students who receive financial aid. If the study would like to construct 90% confidence interval for the proportion of students receiving financial aid within 2%, what sample size would be needed? A previous study stated that 53% of students receive some form of financial aid.

Suppose you are with a health agency that wants to estimate what percentage of Ohioans reallyhas contracted coronavirus and thus has antibodies. If your agency wants a 2% margin of errorat a 95% confidence level, how many people should you have in your study?

Several years ago, 48% of parents who had children in grades K-12 were satisfied with the quality of education the students receive. A recent poll asked 1,035 parents who have children in grades K-12 if they were satisfied with the quality of education the students receive. Of the 1,035 surveyed, 497 indicated that they were satisfied. Construct a 90% confidence interval to assess whether this represents evidence that parents' attitudes toward the quality of education have changed. What are the null and alternative hypotheses? HP versus H₁: p (Round to two decimal places as needed.) Use technology to find the 90% confidence interval. The lower bound is The upper bound is (Round to two decimal places as needed.) What is the correct conclusion? OA. Since the interval contains the proportion stated in the null hypothesis, there is sufficient evidence that parents' attitudes toward the quality of education have changed. OB. Since the interval does not contain the proportion stated in the…

In a sample of 480 adults, 384 had children. Construct a 99% confidence interval for the true population proportion of adults with children. Give your answers as decimals, to three places

A study of 1907 traffic fatalities found that 725 were alcohol related. Suppose you want your 99% confidence interval to be accurate within 1% of the population portion, how many traffic fatalities would need to be in the study?

A poll reported that only 645 out of a total of 2029 adults in a particular region said they had a​ "great deal of​ confidence" or​ "quite a lot of​ confidence" in the public school system. This was down 5 percentage points from the previous year. Assume the conditions for using the CLT are met. Find an 80​% confidence interval and interpret it. The 80​% confidence interval for the proportion that express a great deal of confidence or quite a lot of confidence in the public schools is ____.

Suppose we wish to construct a 95% confidence interval for the population proportion of fans in Notre Dame Stadium on a football Saturday who traveled in their own car. When we asked 200 randomly selected fans, 130 answered yes. Calculate the margin of error for this interval. Round your answer to 3 decimal places.