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Calculating Confidence Intervals

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1. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval for mu, the mean for all such families.

2. A 95% confidence interval estimate for a population mean was computed to be (44.8 to 50.2). Determine the mean of the sample, which was used to determine the interval estimate.

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1. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval for (please see the attached ...

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