Is rest an effecive cure for a headache? A randomized comparative study used highschool students who said they suffer from headaches daily. The researchers assigned 60 of the students to take a nap when they got their next headache and they
randomly assigned the remaining 40 students to receive no special instructions. The researchers found that 45 of the resting
group received relief and that 18 of the no instructions group received relief.
Construct and interpret a 90% confidence interval for the true difference in the proportion of students like these who would
experience relief when resting versus doing nothing special when a headache came on.