13.5 inches equals 34.3 cm. About one centimeter more than our foot. One foot is 33.3 cm. Inch is a common unit of measurement in western countries, and a basic unit of length in English speaking countries. In China, we have our own measurement unit of length, meters and kilometers, as well as Zhang and Ren, which are common but not common. We can't use all our own length units. Why use inches.
