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Level and Width of Confidence Interval of Mean

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Directions:

1) Calculate a point estimate and a 95% confidence interval of the mean. Assuming your data set is normally distributed, determine an appropriate sample size if the maximum allowable error is three units for the attached data set. (Please note: the three units are measure in the unit of measurement of the attached data set eg. hours, pounds, dollars). Use a 90% confidence level to determine the sample size.

2) Interpret the relationship between the level of confidence and the width of the confidence interval.

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This solution shows step-by-step to calculate a point estimate and confidence interval of the mean, it also provides a justified interpretation of the relationship between the level of confidence and width of confidence interval.

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