Question

Using the standard normal distribution, find the two Z-scores forming the middle shaded region.

a) Positive Z-score = ..., Negative Z-score = ...
b) Negative Z-score = ..., Positive Z-score = ...
c) Both Z-scores equal
d) Z-scores not applicable

Answer 1

The two Z-scores forming the middle shaded region can be found using the standard normal distribution. The negative Z-score is -2 and the positive Z-score is 2.

Step-by-step explanation:

The two Z-scores forming the middle shaded region can be found using the standard normal distribution. In the standard normal distribution, about 95 percent of the values lie between z-scores of -2 and 2. Therefore, for a) the positive Z-score is 2 and the negative Z-score is -2. For b) the negative Z-score is -2 and the positive Z-score is 2. For c) both Z-scores are equal, which is not the case here. Therefore, the correct answer is b) Negative Z-score = -2, Positive Z-score = 2.