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OpenStax, Introductory Statistics 2e §6.2 Using the Normal Distribution · Exercise 38 · Statistics · Normal distribution

Using the Normal Distribution · Exercise 38

On average, 28% of 18 to 34 year olds check social media before getting out of bed in the morning. Suppose this percentage follows a normal distribution with a standard deviation of 5%.

(a) Find the probability that the percent of 18 to 34-year-olds who check social media before getting out of bed in the morning is at least 30.
(b) Find the 95^th percentile, and express it in a sentence.

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OpenStax, Introductory Statistics 2e · §6.2 Using the Normal Distribution · Exercise 38

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