* Kilometers to miles: 1 kilometer is approximately 0.621371 miles. So, 20 km is 20 km * 0.621371 miles/km ≈ 12.43 miles
* Liters to gallons: 1 liter is approximately 0.264172 gallons. So, 1 liter is 0.264172 gallons.
* Miles per gallon: Therefore, 20 km/liter is approximately 12.43 miles / 0.264172 gallons ≈ 47.08 miles per gallon