The beauty of the metric system is that it is based on the number 10. . The diagram below shows you a section of a metric ruler. Each numbered line represents one centimeter. . Each small mark after the numbered lines represents one tenth of a centimeter. The larger mark between numbered lines represents five tenths of a centimeter. This allows you to easily see the number of lines over the whole centimeter that an object measures. In the metric system, we always use decimals, never fractions. Instructions 1. Look at the diagram of part of a metric ruler. Above it are some arrows with letters. 2. Look at the letter, determine the measurement and 3. You must always include a unit like centimeter in your answers. You may use abbreviations. Below are some abbreviations for common metric linear measures. Millimeter mm Centimeter Decimeter dm Meter m Kilometre km a. d . g