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Hypothesis Testing: Comparison of Standard deviations

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11.70. According to the National Association of Homebuilders, the average life expectancies of a dishwasher and a garbage disposal are about the same: 10 years. Assume that their finding was based on a sample of n1 = 60 dishwashers and n2 = 40 garbage disposals, and that the corresponding sample standard deviations were s1 = 30 years and s2 = 3.7 years. Using the 0.02 level of significance, examine whether the population standard deviations for the lifetimes of these two types of appliances could be the same.

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The solution provides step by step method for the calculation of testing of hypothesis. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.

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11.70. According to the National Association of Homebuilders, the average life expectancies of a dishwasher and a garbage disposal are about the same: 10 years. Assume that their finding was based on a sample of n1 = 60 dishwashers and n2 = 40 garbage disposals, and that the corresponding sample standard deviations were s1 = 30 years and s2 = 3.7 years. Using the 0.02 level of significance, examine whether the population standard deviations for the ...

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