The consumption of asparagus results in the release of methanethiol and S-methyl thioesters metabolites in the urine. To some people, these metabolites have a very distinctive odor, but others cannot detect the odor ("asparagus anosmia"). How common is asparagus anosmia? In a genetic study aiming to find the genetic markers supporting the phenotype, researchers contacted 6909 participants in a large scientific cohort and found that 4161 had asparagus anosmia. Assuming that the cohort is representative of the American adult population, obtain a 90% confidence interval for the true population of Americans with asparagus anosmia. Use technology, for instance, the 1-PropZInt function in the TI graphing calculator or the Statistics / Proportion / 1-sample function (Confidence Interval tab) on CrunchIt!.