OpenStudy (anonymous):

The average score on a standardized test is 500 points with a standard deviation of 50 points. What is the probability that a student scores between 450 and 600 on the standardized test?

OpenStudy (kropot72):

Do you know how to find the z-scores for 450 and 600?

OpenStudy (anonymous):

No i find it confusing .

OpenStudy (kropot72):

The formula to find the z-score is as follows $z=\frac{X-\mu}{\sigma}$ where X is the reference value (either 450 or 600 in this case), mu is the population average and sigma is the standard deviation. Can you find the 2 z-scores now?

OpenStudy (anonymous):

yes thanckyou it clears up a byt more for me now .

OpenStudy (kropot72):

Do you want to work out the two z-scores and work more through this problem?