A Statistics Professor at a Large University Hypothesizes That Students

question 105

Multiple Choice

A statistics professor at a large university hypothesizes that students who take statistics in the morning typically do better than those who take it in the afternoon. He takes a random sample of 36 students who took a morning class and, independently, another random sample of 36 students who took an afternoon class. He finds that the morning group scored an average of 74 with a standard deviation of 8, while the evening group scored an average of 68 with a standard deviation of 10. The population standard deviation of scores is unknown but is assumed to be equal for morning and evening classes. Let µ₁ and µ₂ represent the population mean final exam scores of statistics' courses offered in the morning and the afternoon, respectively. Compute the appropriate test statistic to analyze the claim at the 1% significance level.

• A) t₇₀ = −2.811
• B) t₇₀ = 2.811
• C) z = −2.811
• D) z = 2.811

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Definitions:

Depression

A severe and prolonged downturn in economic activity, characterized by significant decline in gross domestic product, high unemployment, reduced consumer spending, and deflation.

Inflation

The rate of increase in the average cost of goods and services, which results in a decrease in the value of money.

President Eisenhower

Dwight D. Eisenhower, the 34th President of the United States, who served from 1953 to 1961 and was known for his role in ending the Korean War and promoting infrastructure development.

Recessions

A season of ephemeral economic retreat, observed through decreased levels of commerce and industrial production, commonly distinguished by a fall in GDP in consecutive quarters.