The scores for a recent English exam can be represented by the Normal model N(67,6.3).What score would you expect to be unusually low for this exam?
A)85.9
B)63.85
C)73.3
D)48.1
E)60.7

Question

Quizplus · Accepted Answer

To determine which score would be unusually low, we need to look for a score that is significantly below the mean of 67. An unusually low score would be more than 2 standard deviations below the mean. To calculate this, we subtract 2 times the standard deviation (2*6.3 = 12.6) from the mean: 67-12.6 = 54.4. Therefore, any score below 54.4 would be considered unusually low. The only option that falls below this threshold is D, 48.1.

The Scores for a Recent English Exam Can Be Represented