Assume That Adults Have IQ Scores That Are Normally Distributed

Multiple Choice

Assume that adults have IQ scores that are normally distributed with a mean of 100 and a standard deviation of 15 (as on the Wechsler test) . Find the probability that a randomly selected adult has an IQ between 90 and 120 (somewhere in the range of normal to bright normal) .

A) 0.6014
B) 0.6568
C) 0.6977
D) 0.6227