Posted by Cam on .
A company with two plants producing the same product, but with two slightly different manufacturing processes, conducted a sample study at each of the two plants with the following results: The sample statistics from the first group are: n = 40, xbar = 18, s = 4.2. The sample statistics from the second group are: n = 50, xbar = 20, s = 4. In testing the hypothesis that the mean time to produce the product is the same at both plants, what is the pvalue of the test?

Stats 
Kuai,
Pvalue = P(Z = 2.29) = 0.0219