Final answer:
The outcome is a correct decision, as the null hypothesis H0 was rejected and the true mean value is indeed different from the value stated in H0.
Step-by-step explanation:
The student has asked about a situation in a hypothesis test where the null hypothesis (H0) states that the mean (μ) equals 28. The alternative hypothesis (H1) is that μ is not equal to 28. In the scenario provided, the true value of μ is 29, and H0 was rejected. Considering the definitions of Type I and Type II errors, the outcome in this case is a correct decision, not an error. A Type I error would have occurred if H0 were true, but was rejected. Conversely, a Type II error would have occurred if H0 were false and not rejected. Here, since the null hypothesis is false (the true mean is 29, not 28), and H0 was rejected, the correct decision was made.