An electronics manufacturing process has a scheduled mean completion time of 65 minutes. It is claimed that, under new management, the mean completion time, u, is less than 65 minutes. To test this claim, a random sample of 21 completion times under new management was taken.The sample had a mean completion time of 61 minutes and a standard deviation of 10 minutes. Assume that the population of completion times under new management is normally distributed. At the 0.1 level of significance, can it be concluded that the mean completion time, µ, under new management is less than the scheduled mean?

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