To obtain the area below a positive Z score or above a negative Z score you would________.
A) subtract the value of the Z score from the mean.
B) subtract the area in the "Area Beyond Z" column of the Z score table from 50%.
C) add the value of the Z score to the area beyond the mean.
D) add the area between the Z score and the mean to 50%.

Question

Quizplus · Accepted Answer

To obtain the area below a positive Z score or above a negative Z score, you add the area between the Z score and the mean to 50%. This is because the total area under the normal distribution curve is 100%, and the distribution is symmetric around the mean. Thus, 50% of the area is below the mean. Adding the area between the Z score and the mean to 50% gives the total area below a positive Z score or above a negative Z score.

To Obtain the Area Below a Positive Z Score or Above