Question

Which of the following z-scores indicates the most extreme observation?

A. –4.3.
B. 0.0.
C. 1.9.
D. 3.4.
A score of 84 separates the lowest 75% of the scores from the highest 25% of the scores, and a score of 65 separates the lowest 25% of the scores from the highest 75% of the scores. What is the percentile rank of a score of 84?
A. 25.
B. 65.
C. 75.
D. 84.

Answer 1

Explanation:

Normally Z scores in a std normal distribution curve lie between -3 and 3 comprising more than 99% of total area.

Any entry outside (-3,3) can be considered as an extreme observation.

Here we have hence a) -4.3 is the most extreme observation.

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Given that 84 separates the lowest 75% of the scores from the highest 25% of the scores,

This means 84 is the 75th percentile and similarly 65 is the 25th percentile.

Thus we have 84 has the percentile rank of 75

Option C