posted by nancy .
a sample of 120 men and women randomly divided into 3 groups with 40 people per group. group 1 members varied their workouts. group 2 performed the same exercise at each workout. group 3 had no set schedule or regulations for their workouts. by the end of the study 18 people had dropped out of the first exercise group. estimate the dropout rate for exercises who vary their routine using a 95% confidence interval