What percent of the population scores above 140 on IQ tests?
A)less than 0.5 percent (less than half of one percent)
B)two percent
C)four percent
D)six percent

Question

Quizplus · Accepted Answer

The IQ scale is designed so that the mean is 100 and the standard deviation is 15. A score of 140 is extremely high, falling more than two standard deviations above the mean. According to the empirical rule (or 68-95-99.7 rule) of statistics, 95% of the population falls within two standard deviations of the mean, leaving 5% outside of this range. Since 140 is on the higher end, less than half of that 5% would score above 140, making the correct answer less than 0.5 percent of the population.

What Percent of the Population Scores Above 140 on IQ