1. The problem asks to find the mean deviation of the data set 3, 4, 5, 6, 7, 8. 2. Mean deviation is the average of the absolute deviations from the mean. 3. First, calculate the mean $$\bar{x}$$: $$\bar{x} = \frac{3+4+5+6+7+8}{6} = \frac{33}{6} = 5.5$$ 4. Next, find the absolute deviations from the mean: $$|3 - 5.5| = 2.5$$ $$|4 - 5.5| = 1.5$$ $$|5 - 5.5| = 0.5$$ $$|6 - 5.5| = 0.5$$ $$|7 - 5.5| = 1.5$$ $$|8 - 5.5| = 2.5$$ 5. Sum the absolute deviations: $$2.5 + 1.5 + 0.5 + 0.5 + 1.5 + 2.5 = 9.0$$ 6. Divide by the number of data points (6) to find the mean deviation: $$\text{Mean Deviation} = \frac{9.0}{6} = 1.5$$ 7. Therefore, the mean deviation of the set 3, 4, 5, 6, 7, 8 is 1.5.