SOLUTION: Normal distribution A mean amount of profit per car sold for a sample of 25 dealers was 290$, with a standard deviation of 100$ Develop a 90% Confidence interval for th epopulatio

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Question 240385: Normal distribution
A mean amount of profit per car sold for a sample of 25 dealers was 290$, with a standard deviation of 100$ Develop a 90% Confidence interval for th epopulation mean?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Normal distribution
A mean amount of profit per car sold for a sample of 25 dealers was 290$, with a standard deviation of 100$ Develop a 90% Confidence interval for th epopulation mean?
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sample mean: $290
standard error: 1.645*100/sqrt(25) = 32.9
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90% CI: 290-32.9 < u < 290+32.9
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Cheers,
Stan H.