Lemma
EasyNormal distribution
OpenStax, Introductory Statistics 2e §6.2 Using the Normal Distribution · Example 8 · Statistics · Normal distribution

Using the Normal Distribution · Example 8

a. Calculate the interquartile range (IQR).
b. Forty percent of the smartphone users from 13 to 55+ are at least what age?

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OpenStax, Introductory Statistics 2e · §6.2 Using the Normal Distribution · Example 8

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