Question

Small Sample Mean Problem. The maker of potato chips uses an automated packaging machine to pack its 20-ounce bag of chips. At the end of every shift 18 bags are selected at random and tested to see if the equipment needs to be readjusted. After one shift, a sample of 18 bags yielded the following data. mean = 20.45 s= .80 n = 18. If we were to conduct a test to see if the sample estimate is different from the company's expected weight of 20 oz. at an alpha level = .05, what is (are) the critical t-value(s) for this test?

Answer 1

Degrees of freedom = 18 - 1 = 17

Alpha level = 0.05

This is a two tailed test. Hence,

Critical t values = -2.110, 2.110