The lengths of pregnancies in a small rural village are normally distributed with a mean of 267 days and a standard deviation of 12 days.

In what range would you expect to find the middle 95% of most pregnancies?

Between and

.

If you were to draw samples of size 42 from this population, in what range would you expect to find the middle 95% of most averages for the lengths of pregnancies in the sample?

Between and

.