The body mass index (bmi) of an individual is a measure used to judge whether an individual is overweight or not. a bmi between 20 and 25 indicates a normal weight. in a survey of 750 men and 750 women, the gallup organization found that 203 men and 270 women were normal weight. construct a 90% confidence interval to gauge whether there is a difference in the proportion of men and women who are normal weight. interpret the interval.