The teacher of a sixth-grade class is concerned about the poor academic performance of a 12-year-old student named Nancy. The teacher looks through Nancy's school records and discovers that Nancy got an IQ score of 80 when she took an intelligence test in preschool. Considering the textbook's discussion of IQ scores, the teacher should conclude that:

The teacher should conclude that the girl has an mental age of 9.6 years old, therefore she is not able to understand the classes for 12 years old.

Explanation:

An IQ test is not only to measure your intelligence. It also counts your age to understand if you are above or under your mental's age average. You usually divides the IQ test result with your mental age by your actual age times one hundred. If Nancy is 12 and her IQ is 80, therefore = >

80 = x/12 x 100 = >

x/100 = 80.12 = >

x = 960/100 = 9.6

being x the mental age of the girl.