Exam scores are normally distributed with a standard deviation of 15 points. The population mean is unknown. A random sample of 50 scores has a mean of 80. Construct a 90% confidence interval for the population mean. Use the conf_z_mean function above.
Adapted from Python for Introductory Statistics: Student's Lab Workbook, by Simon Aman (Truman College, City Colleges of Chicago), licensed under CC BY 4.0. Changes were made: reformatted as an accessible XYZ web edition with live in-browser code cells. License: CC-BY-4.0.
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