1. Engineers want to design seats in commercial aircraft so that they are wide enough to fit 99% of all males. Accommodating 100% of males would require very wide seats and that would be too expensive. Men have hip breadths that are normally distributed with a mean of 14.4 in and a standard deviation of 1 inch.

Find P_99, i.e. find the value that separates the smallest 99% from the largest 1%

2.

The lengths of pregnancies re normally distributed with a mean of 268 days and a variance of 225 days. (4^th edition, Triola text)

a. One classical use of the normal distribution is inspired by a letter to Dear Abby , in which a wife claimed to have given birth 308 days after a brief visit from her husband, who was serving in the Navy. Given the information, find the probability of a pregnancy lasting 308 days or longer.

What does this result suggest?

If we stipulate that a baby is premature if the length of pregnancy is in the lowest 4%, find the length that separates premature babies from those who are not premature. Premature babies often require special care and this result would be helpful to hospital administrators in planning for such care.