Hey service station advertises that customers will have to wait no more than 30 minutes for...

Hey service station advertises that customers will have to wait no more than 30 minutes for an oriole change a sample of 28 oil change has a standard deviation of five. Two minutes find the 95% confidence interval of the population variance and standard deviation of the time spent waiting for an oil change

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Expert Solution

95% confidence interval for population variance is

[ 15.627 , 46.3173 ]

95 % confidence interval for standard deviation is

[ 3.9531 , 6.8057 ]

orchestra answered 1 year ago

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