The length of life in hours of a sample of 40 100watt light

The length of life (in hours) of a sample of 40 100-watt light bulbs manufactured in a Sylvania plant and a sample of 40 100-watt light bulbs manufactured in a Phillips plant are contained in tab Bulb Life in the Excel file. In order to analyze the difference in bulb life from these two manufacturers, determine whether the variances are equal and then run the appropriate t-test to test the hypothesis that the mean bulb life of Sylvania bulbs is different than the mean bulb life of Phillips bulbs at the .05 level of significance. State your conclusion and the basis for your conclusion.

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