If raw scores ranging from 1 to 50 represented all the corresponding negative z-scores on the distribution,and raw scores ranging from 50 to 100 represented all the corresponding positive z-scores,what would be the total relative frequency of 50 to 100?
A)1.00
B)0.75
C)0.50
D)0.25

Question

Quizplus · Accepted Answer

Since all the raw scores between 50 to 100 represent positive z-scores, we can calculate the area under the standard normal curve from z = 0 (which corresponds to a raw score of 50) to z = infinity (which corresponds to a raw score of 100). Using a standard normal table or calculator, we find that this area is approximately 0.1915. Since the total area under the standard normal curve is 1, the relative frequency of raw scores between 50 to 100 is:

Relative frequency = area between 50 to 100 / total area = 0.1915 / 1 = 0.50

Therefore, the best choice is C.

If Raw Scores Ranging from 1 to 50 Represented All