Sulfur compounds cause “off-odorsâ€in wine, so winemakers want toknow the odor threshold, the lowest concentration of a compoundthat the human
nose can detect. The odor threshold for dimethyl sulfide (DMS) intrained wine tasters is about 25 micrograms per liter of wine(μg/l). The untrained noses
of consumers may be less sensitive, however. Here are the DMS odorthresholds for 10 untrained students:
31 31 43 36 23 34 32 30 20 24
(a) Assume that the standard deviation of the odor threshold foruntrained noses is known to be σ = 7 μg/l. Briefly discuss theother two “simple conditions,â€
using a stemplot to verify that the distribution is roughlysymmetric with no outliers.
(b) Give a 95% confidence interval for the mean DMS odor thresholdamong all students.
