Root beer was originally made using the sarsaparilla root. However, the oil from this root was shown to be carcinogenic (cancercausing). Since then, many varieties are now made with cane sugar, herbs,...

Root beer was originally made using the sarsaparilla root. However, the oil from this root was shown to be carcinogenic (cancercausing). Since then, many varieties are now made with cane sugar, herbs, spices, and vanilla. Independent random samples of 12-ounce cans of A&W root beer and Barq’s root beer were obtained, and the amount of sugar (in grams) was measured in each. Assume the underlying populations are normal, with unequal variances.

The two-sample t test for comparing population means when the variances are equal is a robust statistical procedure. If the population variances are different, as long as the underlying populations are normal and the sample sizes are equal, then the hypothesis test is still very reliable.