Scores of Adults Aged 60 to 64 on a Common

question 35

Multiple Choice

Scores of adults aged 60 to 64 on a common IQ test are approximately Normally distributed with mean 90 and standard deviation 15.
Suppose we call an IQ of 90 "normal" for adults aged 60 to 64. What percent of the population have "below normal" IQs?

• A) About 50%
• B) Less than 50%
• C) More than 50%
• D) Can't tell from the information given.

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Definitions:

Central Zone

A term that can refer to the central area of a geological feature, a city, or a defined area, known for its significance or distinguishing characteristics.

Regional Elevations

Variations in height or altitude of an area's surface within a specific region, reflecting its topography.

Dense Crust

Refers to parts of the Earth's crust that are made up of heavier, denser materials, often found in oceanic crust compared to continental.

Less Dense Crust

Refers to the Earth's continental crust, which is less dense than oceanic crust, allowing it to float higher on the mantle.