a. The students at Littlewood Regional High School cut an average of 3.3 classes per month. A random sample of 117 seniors averages 3.8 cuts per month, with a standard deviation of 0.53. Are seniors significantly different from the student body as a whole? (HINT: The wording of the research question suggests a two-tailed test. This
b. What if the research question were changed to "Do seniors cut a significantly greater number of classes"? How would the test conducted in problem 7.2a change? (HINT: This wording implies a one-tailed test of significance. How would the research hypothesis change? For the alpha you used in problem 7.2a, what would the value of Z(critical) be?)
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- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
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