6A.7
Sue and Javier are working on a statistics project to estimate the proportion of students at their
school who have a pet dog. Sue selects a random sample of 81 students from the 2,400
students at their school, and Javier selects a separate random sample of 64 students. They will
both construct a 90 percent confidence interval from their estimates. Consider the situation in
which the sample proportion from Sue’s sample is equal to the sample proportion from Javier’s
sample. Which of the following statements correctly describes their intervals?

A) Javier’s interval will have a greater degree of confidence than Sue’s interval will.

B) Sue’s interval will have a greater degree of confidence than Javier’s interval will.

C) The width of Sue’s interval will be the same as the width of Javier’s interval.

D) The width of Sue’s interval will be wider than the width of Javier’s interval.

E) The width of Sue’s interval will be narrower than the width of Javier’s interval