1. **State the problem:** Calculate the mean of the given ungrouped data and round it to the nearest tenth. 2. **Recall the formula for mean:** $$\text{Mean} = \frac{\text{Sum of all data values}}{\text{Number of data values}}$$ 3. **Sort the data (already sorted for clarity):** 3, 4, 6, 10, 10, 12, 12, 13, 13, 13, 13, 16, 16, 16, 16, 17, 17, 18, 18, 20, 21, 22, 22, 23, 23, 26, 27, 27, 30, 30, 31, 32, 34, 34, 35, 35 4. **Count the number of data points:** There are $36$ data points. 5. **Calculate the sum of all data values:** $$3 + 4 + 6 + 10 + 10 + 12 + 12 + 13 + 13 + 13 + 13 + 16 + 16 + 16 + 16 + 17 + 17 + 18 + 18 + 20 + 21 + 22 + 22 + 23 + 23 + 26 + 27 + 27 + 30 + 30 + 31 + 32 + 34 + 34 + 35 + 35 = 732$$ 6. **Calculate the mean:** $$\text{Mean} = \frac{732}{36}$$ 7. **Simplify the fraction:** $$\text{Mean} = \frac{\cancel{732}}{\cancel{36}} = 20.3333...$$ 8. **Round to the nearest tenth:** $$20.3$$ **Final answer:** The mean of the data rounded to the nearest tenth is **20.3**.