Approximately what percentage of scores falls below an IQ score of 130 if the mean of the IQ test is 100 and the standard deviation is 15?
A) 50
B) 30
C) 85
D) None of these

Question

Quizplus · Accepted Answer

An IQ score of 130 is 2 standard deviations above the mean (since each standard deviation is 15 and the mean is 100). In a normal distribution, about 97.5% of scores fall below a score that is 2 standard deviations above the mean. None of the provided options accurately reflects this percentage.

Approximately What Percentage of Scores Falls Below an IQ Score