1. **State the problem:** We want to calculate the weighted mean of responses from 400 respondents who chose among 5 categories: Very Effective (VE), Effective (E), Less Effective (LE), Not Effective (NE), and Don't Know (DK). 2. **Weights assigned:** VE = 5, E = 4, LE = 3, NE = 2, DK = 1. 3. **Formula for weighted mean:** $$\text{Weighted Mean} = \frac{\sum (\text{weight} \times \text{frequency})}{\text{total number of responses}}$$ 4. **Explanation:** Each category's weight is multiplied by the number of respondents who chose it. Then, sum all these products and divide by the total respondents (400). 5. **Example:** Suppose the frequencies are: - VE: $x_1$ - E: $x_2$ - LE: $x_3$ - NE: $x_4$ - DK: $x_5$ Then, $$\text{Weighted Mean} = \frac{5x_1 + 4x_2 + 3x_3 + 2x_4 + 1x_5}{400}$$ 6. **Interpretation:** The weighted mean gives a single value representing the overall effectiveness perception, with higher values indicating more positive responses. *Note: To compute the exact weighted mean, the frequencies $x_1, x_2, x_3, x_4, x_5$ must be known.*