The Random Variable X Is Normally Distributed with Mean of 80

question 30

Short Answer

The random variable X is normally distributed with mean of 80 and standard deviation of 10. What is the probability that a value of X chosen at random will be between 70 and 90?
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Definitions:

Knew-It-All-Along Effect

A cognitive bias where people believe, after an event has occurred, that they predicted or knew the outcome beforehand.

Irrational Treatment

Behavior or actions that lack reason or logical thought, often leading to unfair treatment.

Sunk Costs

Expenses that have already been incurred and cannot be recovered, which should not affect future decision-making but often do.

Faulty Hindsight

The misjudgment of the reasons behind past decisions based on the outcome rather than on the information available at the time.