A researcher knows from the past that the standard deviation of the time it takes to...

A researcher knows from the past that the standard deviation of the time it takes to inspect a car is 16.8 minutes. A random sample of 24 cars is selected and inspected. The standard deviation is 12.5 minutes. At a= 0.05, can it be concluded that the standard deviation has changed? Use the P-value method. Assume the variable is normally distributed.

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orchestra answered 9 months ago

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