Question: A manager of an industrial plant asserts that workers on average do not complete a job using Method A in the same amount of time as they would using Method B. Seven workers are randomly selected. Each worker's completion time (in minutes) is recorded by the use of Method A and Method B.
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a. Specify the null and alternative hypotheses to test the manager's assertion.
b. Assuming that completion times are normally distributed, calculate the value of the test statistic.
c. At the 10% significance level, what is the critical value(s)? What is the decision rule?
d. Is the manager's assertion supported by the data?