Question

1. The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days.

a) Find the 80th percentile of pregnancy length.

b) Find the pregnancy length that separates the upper 30%

c) Find the pregnancy lengths that separate the middle 80%

d) Find the percent of pregnancies that are less than 260 days.

e) Find the percent of pregnancies that are between 250 and 280 days

Answer 1

for o.go vow! 여 z I Z.table/ ro m mener to 0 4 X- M 서 ニ 268 + IS (0-342) (b) uther 3 0304 30° x268 Is (1 282) X ts (1282)

for X= 280 0,798|一0.115) 0.6730 67.3/