TABLE 12-14
A filling machine at a local soft drinks company is calibrated to fill the cans at an average 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 indeed 0.5 ounces. A random sample of 15 cans filled by the machine reveals a standard deviation of 0.67 ounces.
-Referring to Table 12-14, what type of test should be performed?
A) two-tailed test
B) upper-tailed test
C) lower-tailed test
D) none of the above

Question

TABLE 12-14 
A filling machine at a local soft drinks company is calibrated to fill the cans at an average 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 indeed 0.5 ounces. A random sample of 15 cans filled by the machine reveals a standard deviation of 0.67 ounces.
-Referring to Table 12-14, what type of test should be performed?
A) two-tailed test
B) upper-tailed test
C) lower-tailed test
D) none of the above

Quizplus · Accepted Answer

A two-tailed test is appropriate because the company wants to test whether the standard deviation is different from 0.5 ounces, which could be either higher or lower.

TABLE 12-14 A Filling Machine at a Local Soft Drinks Company Is