Brad, a professor in the Walton College of Business, has taught Data Analysis for 3 years Historically, during that time, his average grade is 70% with a standard deviation of 5%. He is disappointed in the results of his students and decides to try different teaching methods to improve their grades. In the spring of 2016, he develops on-line videos as a supplement to his class lecture. During that semester, his average grade is 71% from a sample of 49 students. The level of significance is 2.5%. What hypotheses is Brad testing? 0 H0: μ .70 and HA: μ < .70 0 H0: μ s .71 and HA: μ > .71 0 H0: μ .70 and HA: μ > .70
Accepted Solution
A:
Answer:H0: μ= .70 and HA: μ > .70Step-by-step explanation:Brad wants to test if on-line videos as a supplement to his class lecture improved student's grades. For this he needs to assume H0: μ= .70 and HA: μ > .70 and check if the sample mean is in the critical region in 2.5% confidence level. If it is, then he will reject the null hypothesis in favor of alternative hypothesis. If not, he will fail to reject the null hypothesis.