researcher wishes to​ estimate, with 99​% ​confidence, the population proportion of adults who eat fast food four to six times per week. Her estimate must be accurate within 5​% of the population proportion. ​(a) No preliminary estimate is available. Find the minimum sample size needed. ​(b) Find the minimum sample size​ needed, using a prior study that found that 28​% of the respondents said they eat fast food four to six times per week. ​(c) Compare the results from

Random samples of students at 107 four-year colleges were interviewed several times since 1998. Of the students who reported drinking alcohol, the percentage who reported bingeing at least three times within the past two weeks was 41.1% of 336 students in 1998 and 21.6% of 843 students in 2004. a. Estimate the difference between the proportions in 2004 and 1998, and interpret. b. Find the standard error for this difference. Interpret it. c. Define the two relevant population parameters to compare in the context of this exercise. d. Construct and interpret a 90% confidence interval to estimate the true difference. e. State the assumptions for the confidence interval in part d to be valid. ... A. The number of students in the population in 2004 who reported drinking alcohol that binged at least three times within the past two weeks. B. The proportion of the student population in 1998 who reported drinking alcohol that binged at least three times within the past two weeks. C. The number…

Find the sample​ size, n, needed to estimate the percentage of adults who have consulted fortune tellers. Use a 0.09 margin of​ error, use a confidence level of 98​%, and use results from a prior poll suggesting that 18​% of adults have consulted fortune tellers. n=

Use the given data to find the minimum sample size required to estimate a population proportion or percentage. Margin of error: 0.04; confidence level 90%; p and q unknown n = O (Round up to the nearest integer.)

The average spent nationally on Christmas gifts in 2020 was reported to be $650 per person. Below is a random sample of gift givers from Iowa and what they spent in 2020.    Is there sufficient evidence to conclude that Iowans spend less than the national average?         Estimate the average amount spent by Iowans on Christmas gifts in 2020 with a 90%-CI.     700 450 400 525 550 550 600 575 650 625 500