SOLUTION: Use the normal distribution of SAT critical reading scores for which the mean is 509 and the standard deviation is 118. Assume the variable x is normally distributed. (a) What p

Algebra ->  Probability-and-statistics -> SOLUTION: Use the normal distribution of SAT critical reading scores for which the mean is 509 and the standard deviation is 118. Assume the variable x is normally distributed. (a) What p      Log On


   



Question 1176408: Use the normal distribution of SAT critical reading scores for which the mean is 509 and the standard deviation is 118. Assume the variable x is normally distributed.
(a) What percent of the SAT verbal scores are less than 675?
(b) If 1000 SAT verbal scores are randomly selected, about how many would you expect to be greater than 550?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
z <(x-mean)/.sd
or < (675-509)/118
or < 1.407
that probability is 0.9203
92.0%
-
z>(550-509)/118 or >41/118 or >0.347
that probability is 0.3641
or 364 of the 1000.