Diagrams used to learn how to convert units in the metric system are read by following the arrows in a clockwise direction. The arrow's arch identifies the required action. For example, to convert from kilometers to meters, follow the arrow traveling clockwise between the two. The instructions at the arch read, "x 1,000," indicating the number of kilometers must be multiplied by 1,000 in order to convert to meters.
Continue to follow the clockwise arrows for instructions concerning converting back to the original unit. When looking at the diagram, the arch of the arrow between meters and kilometers shows that the number of meters must be divided by 1,000 in order to convert to kilometers.
The metric system has six different units of measure. Length is measured in meters and volume in liters. Weight is measured in grams. Bar is used as an expression of pressure, while newtons are a measure of force. Temperature is expressed in either Celsius or Kelvin.
Multiples of these units are indicated by prefixes. Deka- indicates a multiple of 10, while hecto- is a multiple of 20. Kilo- is a multiple of 1,000. Separate prefixes are used to denote fractions of the units. Deci- indicates a tenth of unit, centi- is a hundredth, and milli- is a thousandth.