Amanda earned a score of 940 on a national achievement test that was normally distributed. The mean test score was 850 with a standard deviation of 100

Question

If 1000 students took the test, how many scored below Amanda? Use your z table.

Answer 1

1. Compute Amanda's z-score
2. Look up the percentile for her z-score in a z-score table. If you don't have one you can search for one on the internet. They're easy to find.
3. The percentile from step 2 is the percent of test takers who scored lower than Amanda. Multiply the percentile from step 2 by the 1000 students who took the test to get the answer.