1. **State the problem:** Find the mean of the data set: 49, 52, 42, 22, 56, 38, 26, 47, 55. 2. **Formula for mean:** The mean (average) of a data set is given by $$\text{Mean} = \frac{\text{Sum of all data points}}{\text{Number of data points}}$$ 3. **Calculate the sum:** Add all the numbers: $$49 + 52 + 42 + 22 + 56 + 38 + 26 + 47 + 55 = 387$$ 4. **Count the data points:** There are 9 numbers in the data set. 5. **Calculate the mean:** $$\text{Mean} = \frac{387}{9}$$ 6. **Simplify the fraction:** $$\text{Mean} = \frac{\cancel{387}}{\cancel{9}} = 43$$ 7. **Check the calculation:** Since the user mentioned about 38.5, let's re-check the sum: $$49 + 52 + 42 + 22 + 56 + 38 + 26 + 47 + 55 = 387$$ Dividing 387 by 9 gives: $$\frac{387}{9} = 43$$ So the exact mean is 43, not 38.5. **Final answer:** The mean of the data set is **43**.