The following table summarizes the ages of the 400 richest Americans.Suppose we select one of these individuals.Find the probability that the selected individual is less than 80 years old. 
Definitions:
Polygraph Test
A procedure that measures and records several physiological indicators such as blood pressure, pulse, and skin conductivity while the subject answers questions, used to infer truthfulness.
Overall Arousal Levels
A general state of alertness or activation of the nervous system, affecting physical and psychological responses.
Accuracy of Polygraphs
The degree to which polygraph tests can reliably and validly detect deception, often debated in terms of effectiveness.
Seat of Emotions
A metaphorical term that refers to the brain regions responsible for the generation and regulation of emotions, typically involving the limbic system.
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