If one z-score from a distribution is -1 for a raw score of 66 and another z-score is +3 for a raw score of 78, what is the standard deviation for the distribution?
A) 2
B) 4
C) 3
D) 6

Question

Quizplus · Accepted Answer

The standard deviation is 3 because the difference between the two raw scores is 12 (78 - 66), and the difference between the two z-scores is 4 (3 - (-1)). Therefore, each standard deviation unit is equal to 3 raw score points (12 / 4 = 3).

If One Z-Score from a Distribution Is -1 for a Raw