The average weight of a package of rolled oats is supposed to be at least 18 ounces. A sample of 18 packages shows a mean of 17.78 ounces with a standard deviation of 0.41 ounces. The calculated test statistic is t = -2.28 (left tail test) and the corresponding p-value = 0.018. Based on the results above, is the sample mean (17.78 ounces) smaller than the specification (18 ounces) at the 0.05 level of significance? a. Yes, the sample mean is significantly smaller than the specification at 0.05 level of significance.
b. No, the sample mean is not significantly smaller than the specification at 0.05 level of significance.
c. Yes, the p-value is greater than the alpha level.
d. No, the p-value is lower than 0.01