TABLE 12-16
A filling machine at a local soft drinks company is calibrated to fill the cans at a mean amount of 12 fluid ounces and a standard deviation of 0.5 ounces. The company wants to test whether the standard deviation of the amount filled by the machine is 0.5 ounces. A random sample of 15 cans filled by the machine reveals a standard deviation of 0.67 ounces.
-Referring to Table 12-16, there is sufficient evidence to conclude that the standard deviation of the amount filled by the machine is not exactly 0.5 ounces when using a 10% level of significance.

Question

Quizplus · Accepted Answer

In Table 12-16, with a sample size of 14 degrees of freedom (15 - 1), the critical value at a 10% level of significance is 2.145. The calculated test statistic using the sample standard deviation and the hypothesized standard deviation of 0.5 ounces is 2.63. Since 2.63 is greater than 2.145, we reject the null hypothesis and conclude that there is sufficient evidence to support the claim that the standard deviation of the amount filled by the machine is not exactly 0.5 ounces.

TABLE 12-16 A Filling Machine at a Local Soft Drinks Company Is