1. **State the problem:** Caleb wants to find what percent of the total calories in a muffin comes from fat. 2. **Formula:** To find the percentage of calories from fat, use the formula: $$\text{Percentage from fat} = \left(\frac{\text{Calories from fat}}{\text{Total calories}}\right) \times 100$$ 3. **Substitute the values:** $$\text{Percentage from fat} = \left(\frac{30}{200}\right) \times 100$$ 4. **Simplify the fraction:** $$\frac{30}{200} = \frac{\cancel{30}}{\cancel{200}} = \frac{3}{20}$$ 5. **Calculate the percentage:** $$\frac{3}{20} \times 100 = 3 \times 5 = 15$$ 6. **Answer:** 15% of the total calories in a muffin come from fat. Rounded to the nearest whole percent, the answer is **15%**.