There are a few z scores that we use often that are worth remembering. The upper 50%, and 97.5 percent of a normal distribution are cut off by z scores of
A) 1.0, and 1.64.
B) 0.0, and 1.96.
C) .50, and .975.
D) plus and minus 1.96.

Question

Quizplus · Accepted Answer

The upper 50% of a normal distribution is cut off by a z score of 0.0 because the mean (which divides the distribution into upper and lower 50%) corresponds to a z score of 0. The 97.5th percentile corresponds to a z score of 1.96, indicating that 97.5% of the distribution lies below this value.

There Are a Few Z Scores That We Use Often