Assume that the duration of human pregnancies can be described by a normal model with mean 262 days and standard deviation 18 days Complete parts a) through d) below or Page a) What percentage of pregnancies should last between 26 and 275 days? % (Round to one decimal place as needed.) b) Al least how many days should the longest 30% of all pregnancies last? Pxz)-0,30 (Round to one decimal place as needed) c) Suppose a certain obstetrician is currently providing prenatal care to 80 pregnant women. Let y represent the mean length of their pregnancies According to the central limit theorem what is the mean and standard deviation SDL) of the nomal model of the distribution of the sample mean y The meanis 306) (Round to two decimal places as needed) d) What is the probability at the mean duration of the patients' pregnancies wil below than 200 days
