Author Question: The sample mean for a recent introductory psychology test was 78 and the sample variance was 9 . ... (Read 52 times)

OSWALD · **on:** Jun 20, 2018

The sample mean for a recent introductory psychology test was 78 and the sample variance was 9 . Approximately what proportion of the scores was above 81?

a. 0.50 c. 0.16
b. 0.68 d. 0.34

Question 2

Using the appropriate values from the z-table in the textbook appendix, find the z-score for which the area beyond z in the tail is 0.2546.

a. 0.66 c. 0.66
b. 0.2454 d. 0.2454