#11

A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1472

and the standard deviation was 310. The test scores of four students selected at random are 1900, 1220 2200, and 1360. Find the z-scores that correspond to each value and determine whether any of the values are unusual.

The z-score for 1900 is ________ (Round to two decimal places as needed)

#15

Assume the random variable x is normally distributed with mean =50 and standard deviation =7.

Find the indicated probability.

P(x>38)= _______ (Round to four decimal places as needed)