Assuming that on average college students in the U.S. send 120 text messages per day. A...

Assuming that on average college students in the U.S. send 120 text messages per day. A researcher wants to examine if the amount of text messages sent daily by UNC students differs from the national average. The researcher took a sample of 64 UNC students, and finds that the mean number of texts per day is 126 with a standard deviation of 24. Use alpha .05

a) Is this a one-tail or two-tail test? Write appropriate hypotheses and assumptions.
b) Determine the degree of freedom and the critical value for this test.
c) Calculate the standard error.
d) Calculate the test statistics and determine its P-value.
e) State your conclusion by comparing the critical value to the test statistic and by comparing P to alpha.

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orchestra answered 11 months ago

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