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Confidence interval for mean

The association of coffee growers in Puerto Rico wants to know the average pounds of coffee consumption per week in towns in the metropolitan area. In a study conducted recently by the average of 81 persons was 1.5 pounds a week and a standard deviation of 0 .10.

1) What is the value of the average population?
2) What distribution we have to use, z or t?
3) What is the value of t for a confidence level of 95%?
4) Construct a confidence interval of 95% for the population mean.

Solution Summary

The solution provides step by step method for the calculation of confidence interval for mean . Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.