Twenty-eight small communities in Connecticut (population near 10,000 each) gave an average of x = 138.5 reported cases of larceny per year. Assume that σ is known to be 40.5 cases per year
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| margin of error |
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| upper limit | |
| margin of error |
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| margin of error |
+33654 Assuming the distribution of larceny cases is normal (Gaussian), then the following information should help you to answer the question.
±1.282 standard deviations away from the mean define a 90% confidence interval.
±1.645 standard deviations away from the mean define a 95% confidence interval.
±2.326 standard deviations away from the mean define a 99% confidence interval.
The margin of error is half the confidence interval (so for the 90% case here, for example, the margin of error is 1.282*40.5; unless the 40.5 is meant to be the sample σ, in which case the population σ is 40.5/√28 ≈ 7.65 and should be used instead of 40.5)
+33654 Assuming the distribution of larceny cases is normal (Gaussian), then the following information should help you to answer the question.
±1.282 standard deviations away from the mean define a 90% confidence interval.
±1.645 standard deviations away from the mean define a 95% confidence interval.
±2.326 standard deviations away from the mean define a 99% confidence interval.
The margin of error is half the confidence interval (so for the 90% case here, for example, the margin of error is 1.282*40.5; unless the 40.5 is meant to be the sample σ, in which case the population σ is 40.5/√28 ≈ 7.65 and should be used instead of 40.5)
