Under the normal curve, between the z scores of + 1 and + 2, there are always
A) 68% of the cases
B) 95% of the cases
C) 13.50% of the cases
D) sometimes a, and sometimes b, but never c

Question

Quizplus · Accepted Answer

Between the z scores of +1 and +2 on a normal distribution curve, there are approximately 13.5% of the cases. This is because the area between the mean (0) and +1 z score is about 34.13%, and between the mean and +2 z score is about 47.72%. Subtracting these percentages gives the area specifically between +1 and +2 z scores.

Under the Normal Curve, Between the Z Scores of