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In Exercises 12.49–12.54, use Procedure 12.1 on page 548 to find the required confidence interval. Be sure to check the conditions for using that procedure.
12.51 Asthmatics and Sulfites. In the article “Explaining an Unusual Allergy” appearing on the Everyday Health Network, Dr. A. Feldweg explained that allergy to sulfites is usually seen in patients with asthma. The typical reaction is a sudden increase in asthma symptoms after eating a food containing sulfites. Studies are performed to estimate the percentage of the nation’s 10 million asthmatics who are allergic to sulfites. In one survey, 38 of 500 randomly selected U.S. asthmatics were found to be allergic to sulfites. Find and interpret a 95% confidence interval for the proportion, p, of all U.S. asthmatics who are allergic to sulfites.
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Introductory Statistics (10th Edition)
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