Determine the two z-scores that separate the middle 87.4% of the distribution from the area in the tails of thestandard normal distribution.
A) -1.53, 1.53
B) -1.39, 1.39
C) -1.46, 1.46
D) -1.45, 1.45

Question

Quizplus · Accepted Answer

The middle 87.4% of the distribution leaves 12.6% in the tails, which is divided equally into 6.3% in each tail. Looking up 6.3% in the z-table or using a calculator to find the z-score that corresponds to the cumulative area of 0.937 (1 - 0.063) gives a z-score of approximately ±1.53.

Determine the Two Z-Scores That Separate the Middle 87