SOLUTION: Assume that the mean length of a human pregnancy is 268 days with a standard deviation of 9 days. What precentage of human pregnancies do we expect to last no more than 260 days?
Algebra ->
Probability-and-statistics
-> SOLUTION: Assume that the mean length of a human pregnancy is 268 days with a standard deviation of 9 days. What precentage of human pregnancies do we expect to last no more than 260 days?
Log On
Question 744080: Assume that the mean length of a human pregnancy is 268 days with a standard deviation of 9 days. What precentage of human pregnancies do we expect to last no more than 260 days? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Assume that the mean length of a human pregnancy is 268 days with a standard deviation of 9 days. What precentage of human pregnancies do we expect to last no more than 260 days?
------------
z(260) = (260-268)/9 = -8/9
-----
P(x <= 260) = P(z <= -8/9) = normalcdf(-100,-8/9) = 0.1870
==========================
Cheers,
Stan H.