Example Exercise: 4.19 (OpenIntro Statistics), 4.35 (Advanced High School Statistics)

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We learned in a previous exercise that about 70% of 18-20 year olds consumed alcoholic beverages in 2008. We now consider a random sample of fifty 18-20 year olds.
(a) How many people would you expect to have consumed alcoholic beverages? And with what standard deviation?
(b) Would you be surprised if there were 45 or more people who have consumed alcoholic bever- ages?
(c) What is the probability that 45 or more people in this sample have consumed alcoholic beverages? How does this probability relate to your answer to part (b)?

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These are different values than shown in Appendix A of the book for the answers. In both the hardback print and pdf.