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.

Step-by-step 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.

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

9/2

Step-by-step explanation:

2(3x - 1) = 25

6x - 2 = 25

6x = 27

x = 9/2