# Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean μ=272 days and standard deviation σ=19 days. What is the probability that a random sample of 51 pregnancies has a mean gestation period of 265 days or​ less?

Question
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean μ=272 days and standard deviation σ=19 days.

What is the probability that a random sample of 51 pregnancies has a mean gestation period of 265 days or​ less?