1. **State the problem:** Malcolm lost 8 kg and now weighs 64 kg. We need to find what percentage of his original weight he lost. 2. **Identify the known values:** - Weight lost = 8 kg - Current weight = 64 kg 3. **Find the original weight:** Since Malcolm lost 8 kg and now weighs 64 kg, his original weight was: $$\text{Original weight} = 64 + 8 = 72 \text{ kg}$$ 4. **Use the percentage formula:** The percentage of the original weight lost is given by: $$\text{Percentage lost} = \left(\frac{\text{Weight lost}}{\text{Original weight}}\right) \times 100$$ 5. **Substitute the values:** $$\text{Percentage lost} = \left(\frac{8}{72}\right) \times 100$$ 6. **Simplify the fraction:** $$\frac{8}{72} = \frac{\cancel{8}^1}{\cancel{8}^9} = \frac{1}{9}$$ 7. **Calculate the percentage:** $$\text{Percentage lost} = \frac{1}{9} \times 100 \approx 11.11\%$$ **Final answer:** Malcolm lost approximately **11.11%** of his original weight.