# IQ Intelligence quotient

Intelligence quotient (IQ) is a standardized score used as the output of standardized intelligence psychological tests to quantify a person's intelligence with the rest of the population (respectively, to a given group). Intelligence has an approximately normal distribution. Today, the most commonly used deviation score is with a population average of 100 and a population standard deviation of 15. What is the probability that a randomly selected person from the population has an IQ of less than 85?

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