To assess the efficiency of the cars listed, we can examine their fuel economy in terms of kilometers traveled per unit of weight (efficiency in terms of weight).
Here are the calculations for each option, using kilometers per liter (km/L) divided by weight (kg):
-
900 kg car that travels 15 km per liter:
- Efficiency = \( \frac{15 \text{ km/L}}{900 \text{ kg}} \) = 0.0167 km/(L*kg)
-
1,200 kg car that travels 20 km per liter:
- Efficiency = \( \frac{20 \text{ km/L}}{1200 \text{ kg}} \) = 0.0167 km/(L*kg)
-
1,200 kg car that travels 15 km per liter:
- Efficiency = \( \frac{15 \text{ km/L}}{1200 \text{ kg}} \) = 0.0125 km/(L*kg)
-
900 kg car that travels 20 km per liter:
- Efficiency = \( \frac{20 \text{ km/L}}{900 \text{ kg}} \) = 0.0222 km/(L*kg)
Now, comparing the efficiencies we calculated:
- \( \frac{15}{900} = 0.0167 \)
- \( \frac{20}{1200} = 0.0167 \)
- \( \frac{15}{1200} = 0.0125 \)
- \( \frac{20}{900} = 0.0222 \)
The car with the greatest efficiency is the 900 kg car that travels 20 km per liter of fuel, with an efficiency of 0.0222 km/(L*kg).