SOLUTION: The mark 'x' of an exam is normally distributed with a mean of 64 and a standard deviation of 8. If 200 students take the exam, how many students would you expect to obtain a mark
Algebra ->
Probability-and-statistics
-> SOLUTION: The mark 'x' of an exam is normally distributed with a mean of 64 and a standard deviation of 8. If 200 students take the exam, how many students would you expect to obtain a mark
Log On
Question 581557: The mark 'x' of an exam is normally distributed with a mean of 64 and a standard deviation of 8. If 200 students take the exam, how many students would you expect to obtain a mark between 64 and 80?
Thank you so much for your help Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! The mark 'x' of an exam is normally distributed with a mean of 64 and a standard deviation of 8. If 200 students take the exam, how many students would you expect to obtain a mark between 64 and 80?
---------
z(64) = 0
--
z(80) = (80-64)/8 = 16/8 = 2
--------
P(60<= x <=64) = P(0<= z <=2) = normalcdf(0,2) = 0.4772
======================
Cheers,
Stan H.
----------------