A Sample of 200 Observations Is Taken

question 41

Multiple Choice

A sample of 200 observations is taken.The mean is 31.7 and the standard deviation is 1.8.Form a 90 percent confidence interval for the population mean.

• A)[31.54 31.86]
• B)[28.74 34.66]
• C)[28.53 34.87]
• D)[31.49 31.91]