MediumNormal distribution

OpenStax, Introductory Statistics 2e §6.2 Using the Normal Distribution · Exercise 24 · Statistics · Normal distribution

Using the Normal Distribution · Exercise 24

IQ is normally distributed with a mean of 100 and a standard deviation of 15. Suppose one individual is randomly chosen. Let X = IQ of an individual.

(a) X ~ _____(_____,_____)
(b) Find the probability that the person has an IQ greater than 120. Include a sketch of the graph, and write a probability statement.
(c) MENSA is an organization whose members have the top 2% of all IQs. Find the minimum IQ needed to qualify for the MENSA organization. Sketch the graph, and write the probability statement.
(d) The middle 50% of IQs fall between what two values? Sketch the graph and write the probability statement.

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OpenStax, Introductory Statistics 2e · §6.2 Using the Normal Distribution · Exercise 24

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