Engineers want to design seats in commercial aircraft so that they are wide enough to fit 90 % of all males. (Accommodating 100% of males would require very wide seats that would be much too expensive.) Men have hip breadths that are normally distributed with a mean of 14.9 in. and a standard deviation of 1.1 in. Find Upper P 90 . That is, find the hip breadth for men that separates the smallest 90 % from the largest 10 %. The hip breadth for men that separates the smallest 90 % from the largest 10 % is Upper P 90 is.