A Student Wanted to Quickly Construct a 95% Confidence Interval

question 99

Multiple Choice

A student wanted to quickly construct a 95% confidence interval for the average age of students in her statistics class. She randomly selected 9 students. Their average age was 19.1 years with a standard deviation of 1.5 years. What is the 99% confidence interval for the population mean?

• A) [17.42, 20.78]
• B) [17.48, 20.72]
• C) [14.23, 23.98]
• D) [0.44, 3.80]
• E) [17.95, 20.25]

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Definitions:

Predicted Values

Estimates or forecasts of a variable or outcome based on a model or analysis of correlated variables.

Actual Y Values

The observed values of the dependent variable in a data set or experiment, compared against predicted values in regression analysis.

Estimated Regression Line

A line calculated from the data that best fits the relationship between the independent variable(s) and the dependent variable, used to predict the value of the dependent variable from the independent variable(s).

Slope

The steepness of a line on a graph, representing the rate of change, calculated as the rise divided by the run between two points on the line.