# Confidence interval of populations

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Details: Refer to the OECD data, which reports information on census, economic, and business data for 29 countries.

a. Develop a 90 percent confidence interval for the mean percent of the population over 65 years.

b. Develop a 90 percent confidence interval for the mean energy use.

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Z value for 90% confidence = 1.28 ( Normal Tables)

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<br>90% confidence Interval = (Mean - Z* Std Dev , Mean + Z* ...

###### Education

- BE, Bangalore University, India
- MS, University of Wisconsin-Madison

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