Article about the amount of adults who smoke in the state of Wisconsin. The confidence interval was (20.7, 1.1). Meaning that the mean of the estimate is 20.7% of the population and 1.1% is the variation in the estimate. This particular confidence interval is a 95% confidence interval and the sample size was 200. This confidence interval means that almost a quarter of the population in Wisconsin smoke cigarettes. It is also note worthy that the variation is quite low at 1.1.

How do you think the confidence interval that was presented in the study was calculated?