1. **State the problem:** Han ran 12,500 meters last week. We need to convert this distance into kilometers. 2. **Recall the conversion rule:** 1 kilometer (km) equals 1,000 meters (m). So, to convert meters to kilometers, divide the number of meters by 1,000. 3. **Set up the conversion:** $$\text{kilometers} = \frac{\text{meters}}{1000}$$ 4. **Substitute the given value:** $$\text{kilometers} = \frac{12500}{1000}$$ 5. **Simplify the fraction:** $$\text{kilometers} = \frac{\cancel{12500}}{\cancel{1000}} = 12.5$$ 6. **Interpret the result:** Han ran 12.5 kilometers last week. **Final answer:** Han ran **12.5 kilometers** last week.