How many?

Kilometres

The kilometre, or kilometer in American English, is a unit of length in the metric system, equal to one thousand metres. Many people know a marathon race is 26.2 miles long but did you know that a marathon is 42.195 in kilometres?

Inches

The inch is a unit of length in the British imperial and the United States customary systems of measurement. Since the adoption of the international yard during the 1950s and 1960s it has been based on the metric system and defined as exactly 25.4 mm. The standard size pencil that you may see in schools and offices is 7 inches long.