The Wechsler Adult Intelligence Scale (WAIS) is the most common IQ test. The distribution of scores for adults taking the WAIS is approximately Normal with a mean of 100 and a standard deviation of 15.

Use the 68-95-99.7 rule to answer the question about WAIS scores.

What percentage of adults score above 100?

A. 84%
B. 68%
C. 32%
D. 0.3%
E. 50%
F. 2.5%

Using the 68-95-99.7 rule, the percentage of adults scoring above 100 on the Wechsler Adult Intelligence Scale (WAIS) is 50%, as the distribution is symmetrical around the mean IQ score of 100.

Explanation:

The Wechsler Adult Intelligence Scale (WAIS) is used to measure intelligence in adults and follows a normal distribution with a mean IQ score of 100 and a standard deviation of 15. The 68-95-99.7 rule, also known as the empirical rule, states that about 68% of values fall within one standard deviation of the mean in either direction, about 95% within two standard deviations, and about 99.7% within three standard deviations.

According to this rule, if the mean IQ score is 100, then 50% of scores would be above the mean and 50% would be below, since the normal distribution is symmetrical around the mean. Therefore, the percentage of adults who score above 100 on the WAIS would be 50%.