# Statistics

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It is known that the amount of time needed to change the oil in a car is normally distributed. A random sample of 100 oil changes yielded a sample mean of 22 minutes and a standard deviation of 5 minutes. Then compared to the interval estimate for the previous question. This 99% confidence interval estimate of the mean of the population would be -

identical
much more precise
a bit more precise
a bit less precise
much less precise

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