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Du may need to use the appropriate appendix table or technology to answer this question. A sample of 121 checked bogs at an expert had an average weight of 39. pounds with a standard deviation of 7 pounds.

(a) At 95% confidence, compute the margin of error (in pounds), (Round your answer to tour decimal placks)

Explain what it says.

Approximately 95% of all samples of value 121 will propose a sample mean and margin of error such that the distance between the sample mean and the population means it is at moat me march of error.

We can say with 0.95 probability that the distance between the sample mean of 39 pounds and the population mean is at least the margin of error calculated above.

We can say wet 0.95 is probably the population that the ounce between the sample mean of 39 pounds and the population mean is at most the margin of error calculated above.

Approximately 95% of all samples of Bire 121 will produce a sample mean and margin of error such that the database between the same mean and the population mean is at least the march of error

Approximately 95% of all samples of sire 121 will produce a sample mean and margin of error so that the distance between the sample means and the population mean is equal to the Apargin of error.

(b) Determine a 95% confidence interval for the population mean weight of checks at the airport (in pounds). (Faund your answers to two decimal places) tos to

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Final answer:

The margin of error at a 95% confidence level is calculated using the z-score for the desired confidence level, the sample standard deviation, and the sample size. This margin of error, once determined, is used to construct the confidence interval for the population mean weight around the sample mean.

Step-by-step explanation:

To compute the margin of error for a sample mean at 95% confidence, we use the formula: Margin of Error = (z-value) * (standard deviation / sqrt(n)), where z-value is the z-score corresponding to your confidence level, standard deviation is the standard deviation of your sample, and n is your sample size.

Given a sample size of n = 121, a sample mean of 39 pounds, and a standard deviation of 7 pounds, you would use the z-score for 95% confidence, which is approximately 1.96.

Plugging these numbers into the formula yields the margin of error. Once you've calculated the margin of error, you can create the confidence interval for the population mean weight, which is the sample mean plus or minus the margin of error.

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