1. **Stating the problem:** We have a frequency distribution of marks obtained by students and are asked to find the assumed mean using the class with the highest frequency. 2. **Identify the class with the highest frequency:** The frequencies are 11, 29, 36, 22, and 8 corresponding to classes 0-10, 10-20, 20-30, 30-40, and 40-50 respectively. 3. **Find the highest frequency:** The highest frequency is 36 in the class 20-30. 4. **Determine the assumed mean:** The assumed mean is typically the midpoint of the class with the highest frequency. 5. **Calculate the midpoint of class 20-30:** $$\text{Midpoint} = \frac{20 + 30}{2} = \frac{50}{2} = 25$$ **Final answer:** Assumed mean = $25$