The yield of a chemical process is being studied. From previous experience with this process the standard deviation of yield is known to be 3. The past 5 days of plant operation have resulted in the following yields: 91.6, 88.75, 90.8, 89.95, and 91.3%. Use alpha=0.05.
(a) Is there evidence that the mean yield is not 90%?
(b) What is the P-value for this test?
(c) What sample size would be required to detect a true mean yield of 85% with probability 0.95?
(e) Find a 95% two-sided CI on the true mean yield.
(f) Use the CI found in part e to test the hypothesis.
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To start out, I need help choosing what my H0 and H1 should be.