To estimate the true proportion of students who abstain from alcohol at LBCC, you will need to take a simple random sample.
a) How large a sample would you need if you want your estimate to be within .03 of the true value with a 97% confidence level and you know nothing about the population?
b) Repeat part (a) except now you know that a previous study found that 19% of college students abstain from alcohol.
c) For a sample size 96, you came up with a confidence interval of (.159, .241). What is the confidence level of this interval?
d) Using the information in part (c), create a 99% confidence interval.