We have converted 21 Miles per Gallon to 13.5 Litres per 100 kilometres.
21 MPG = 13.5
Fuel Consumption Converter
Use this tool to convert car fuel consumption from Miles per Gallon (MPG) to Litres per 100 kms. Find out the fuel (petrol or diesel) consumption of a car if it is defined in units you do not use or understand.