A technical training firm claims that the average time for their trainees to master a particular skill is 40 hours. To maintain this average, 24 students are tested every month. If the computed t-value falls between −?0.025 and ?0.025, the firm is satisfied with its claim. What conclusion should the firm draw from a sample that has a mean of ?̅= 42 hours and a standard deviation of ? = 6 hours? Assume the distribution of the training time to be approximately normal.

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