Scores of an IQ test have a bell-shaped distribution with a
mean of 100 and a standard deviation of 14. Use the
empirical rule to determine the following.
(a) What percentage of people has an IQ score between 72
and 128?
(b) What percentage of people has an IQ score less than 86
or greater than 114?
(c) What percentage of people has an IQ score greater than
142?
