## Conversion of Units

Sometimes it is necessary to convert units from one measurement system to another or convert within a system (for example, from kilometers to meters).
For Example, conversion factors between SI and U.S. customary units of length are as follows:
`1 mi l e = 1,609 m = 1.609 km`
`1 m = 39.37 i n. = 3.281 ft`
`1 ft = 0.304 8 m = 30.48 cm`
`1 i n. = 0.0254 m = 2.54 cm (exactly)`