Historically, the proportion of adults over the age of 24 who smoke has been 0.30. A more recent sample of 500 adults revealed only 25% of those sampled smoked. A) Develop a 98% confidence interval for the proportion of adults who currently smoke. B) Is this confidence interval less than the historic average? [Hint: Large sample.]
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25), z is the z-score corresponding to the desired confidence level (98% corresponds to a z-score of 2.33), and n is the sample size (500). Plugging in the values, we get: CI = 0.25 ± 2.33*√(0.25*(1-0.25)/500) CI = 0.25 ± 0.052 CI = (0.198, 0.302) Show more…
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