#16

Assume the random variable x is normally distributed with mean =90 and standard deviation =5. Find the indicated probability. P(74

P(74

#20

Use the normal distribution of SAT critical reading scores for which the mean is 501 and the standard deviation is 120. Assume the variable x is normally distributed.

(a)	What percent of the SAT verbal scores are less than 650?
(b)	If 1000 SAT verbal scores are randomly selected, about how many would you expect to be greater than 550?