Problem regarding the sample standard deviation

Reference no: EM13985500

A manufacturer claims that the mean life of batteries manufactured by his company is at least 44 months. A random sample of 40 of these batteries was tested, resulting in a sample mean life of 41 months with a sample standard deviation of 16 months. Test at α = 0.01 whether the manufacturer's claim is correct.

Reference no: EM13985500

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