Questions on a statistics exam are considered good questions provided the questions discriminate between students who have studied for the exam and those who have not studied. Suppose that on a particular statistics exam the students were separated into two groups, the group that studied and theother group that had not studied. Data was collected and a 95% confidence interval for the difference in the proportion of those passing the examfrom the group that studied and the proportion of those passing the exam from the group that had not studied. The confidence interval turned out to be(0.005,0.125).Note that sample 1 is from the group that studied and sample 2 is from the group that did not study. Select the best answer. Select one: A. We are 95% confidence that there is no statistically significant difference between passing rates of those who studied and those who did not study. B. We are 95% confident that those who studied had a higher passing rate than those who did not study. C. We are 95% confident that those who studied had a lower passing rate than those who did not study. D. None of the these are correct.

The U.S. Food and Drug Administration(FDA) performed a study that compared the carbohydrate content (as a percentage of weight) of several major brands ofcorn andpotato chips. Fourteen brands of corn chips were sampled and 14 brands of potato chips were sampled. Data was collected and the following 95% confidence interval was computed for the difference in means.Intrepret the 95% confidence interval for the difference in the mean carbohydrate content between the Corn Chip and Potato Chip groups.

The C.I. is:(27.292,39.836)

where1= the average carbohydrate content as a percentage of weight in corn chips.

and2= the average carbohydrate content as a percentage of weight inpotato chips.

Select the best answer below.

Select one:

A. We are 95% confident that there is no statistically significant difference in the average carbohydrate content as a percentage of weight between corn chips and potato chips.B. We are 95% confident that the average carbohydrate content as a percentage of weight in corn chips is lower than the average carbohydrate content as a percentage of weight in potato chips.C. We are 95% confident that the average carbohydrate content as a percentage of weight in corn chips is higher than the average carbohydrate content as a percentage of weight in potato chips.D. None of these are correct