題組內容

3. Two machines are used for filling plastic bottles with a net volume of 650 ml. The filling processes can be assumed to be normal, and the two standard deviations are unknown but equal. The quality engineering department suspects that whether or not the filling volume is 650 ml. An experiment is performed by taking a random sample of 10 bottles from each machine.
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(a) Assume the mean filling volumes of two machines are the same. Please state the hypotheses that should be tested in this experiment. (2 points)