What proportion of the standardized scores of a sample lies between the Z-scores of -1.96 and +1.96?
A)34.0%
B)47.7%
C)68.3%
D)95.5%

Question

Quizplus · Accepted Answer

Z-scores are a common standardized score used to express deviations from the mean in terms of standard deviation units. Figure 12-1 demonstrates that standardized scores lying between the Z-score of -1.96 and +1.96 are distributed over 95.5% of the normal curve.
34.0% of cases will be 1 score above or below the mean.
Approximately 47.7% of cases will be 1.96 above OR below the mean.
68.3% of cases will lie between the Z-scores of -1.0 and +1.0.

What Proportion of the Standardized Scores of a Sample Lies