A Statistics Professor at a Large University Hypothesizes That Students

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. Which of the following hypotheses will test the professor's claim?

A) H₀: µ₁ - µ₂ ≤ 0, H_A: µ₁ - µ₂ > 0
B) H₀: µ₁ - µ₂ ≥ 0, H_A: µ₁ - µ₂ < 0
C) H₀: µ₁ - µ₂ > 0, H_A: µ₁ - µ₂ ≤ 0
D) H₀: µ₁ - µ₂ = 0, H_A: µ₁ - µ₂ ≠ 0