Question

The average score on a standardized test is 750 points with a standard deviation of 50 points. If 2,000 students take the test at a local school, how many students do you expect to score between 700 and 800 points?


1130

1200

1360

1500

Answer 1

P (700 < x < 800) = P (-1 < z < 1) = 0.6827

0.6827*2000 = 1365.4
so it would be 1360

Answer 2

I have one last one:


Suppose you have a mean standardized score of 1500 points with a standard deviation of 150 points. This data is normally distributed. What is the z-score of 1300 points?


–0.65

–1.33

–1.50

–1.56

Answer 3

1300 - 1500
------------- = -200/150 = -1.33
. 150


A. –0.65
B. –1.33 <==ANSWER
C. –1.50
D. –1.56