A researcher selects a sample of 6 professors, 6 students, and 6 administrators at a local school and has them rate the effectiveness of an innovative new teaching style. In this example, is it possible that the weighted mean ratings will equal the arithmetic mean for the entire sample of 18 participants?
A. No, the weighted mean is never exactly equal to the arithmetic mean.
B. Yes, because there are an even number of participants in each sample.
C. Yes, because the sample sizes are equal in this example.
D. It is not possible to know this without knowing the mean for each sample.