A survey conducted in year 2021 suggested that 210 out of 300 (70 percent) of university students worked in the summer of 2021. A similar survey is planned for year 2022. Researchers beleve that the 70 percent fraction will remain unchanged. They wish to construct a 90 percent confidence Interval for the difference in proportions and wish to ensure a margin of error at 5 percent. Find the required sample size for the 2022 survey,

Suppose you work for the Department of Environment and National Resources (DENR). You want to estimate, with 95% confidence, the mean length of all tilapia in a fish hatchery pond. You take a random sample of 10 tilapia and determine the average length is 10.5 inches and the sample standard deviation is 2.9 inches. Construct a confidence interval for this sample and interpret the result.

An internet study was mailed to 2336 subjects randomly. 1108 surveys were returned. Construct a 95% confidence interval for the proportion of the returned surveys. identify the margin of error E.

Consider the sample dataset : 2,4,5,9,10.    What is point estimate and sample standard deviation? What is margin of error at 95% confidence level? Calculate confidence intervals at 95% confidence level.