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In: Statistics and Probability

It is believed that an electronic device has an average lifetime which is less than or...

It is believed that an electronic device has an average lifetime which is less than or equal to 4 years. A sample of 14 such devices was run until failure, and the average lifetime was found to be 3.56 years with a variance of 1.12. The p-value for the hypothesis test is approximate:

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Expert Solution

This is a two-tailed test

Test statistic

                   

                    = -1.556

P-value = 2 * P(T < -1.556) = 0.0719

orchestra answered 2 years ago
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