Lemma
EasyNormal distribution
OpenStax, Introductory Statistics 2e §6.2 Using the Normal Distribution · Try It 4 · Statistics · Normal distribution

Using the Normal Distribution · Try It 4

Use the information in to answer the following questions.

(a) Find the 30^th percentile, and interpret it in a complete sentence.
(b) What is the probability that the age of a randomly selected smartphone user in the range 13 to 55+ is less than 27 years old.

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OpenStax, Introductory Statistics 2e · §6.2 Using the Normal Distribution · Try It 4

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