Question

Researchers are testing commercial air filtering systems made by the Winston Industrial Supply Company and the Barrington Filter company. Random samples are tested for each company, and the filtering efficiency is scored on a standard scale, with the results shown. (Higher scores correspond to better filtering.)

Winston: n = 18, sample mean = 85.7, and sample standard deviation = 5.8.

Barrington: n = 24, sample mean = 80.6, and sample standard deviation = 6.1.

(a) At the 0.05 significance level, test the claim that both systems have the same mean.

Original claim is made by Answer hypothesis.
Original claim is: Mean_WISC - Mean_BFCAnswer 0.
Test statistic: Answer
Critical value:±Answer
P-value: Answer
Initial conclusion: We Answer the null hypothesis.
Final conclusion: There Answer enough evidence to warrant the rejection of the claim.

Answer 1