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Sample size for estimating a population mean

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An estimate is needed of the mean acreage of farms in Manitoba, Canada. The estimate should be correct to within 100 acres with probability 0.95. A preliminary study suggests that 500 acres is a reasonable guess for the standard deviation of farm size.

How large a sample of farms is required and given that random sample size found, The sample has a standard deviation of 300 acres, rather than 500. What is the margin of error for a 95% confidence interval for the mean acreage of farms?

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Solution Summary

This solution shows how to determine the sample size necessary to construct a confidence interval for a population mean when the margin of error must be within a given amount and the interval must have a given level of confidence.

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An estimate is needed of the mean acreage of farms in Manitoba, Canada. The estimate should be correct to within 100 acres with probability 0.95. A preliminary study suggests that 500 acres is a reasonable guess for the standard deviation of farm size.

How large a sample of farms is required and given that random sample size found.The sample has a standard deviation of 300 acres, rather than 500. What is the margin of error for a 95% confidence interval for the mean acreage of farms?

In this problem, we want to use the sample mean, to estimate the ...

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