This math topic focuses on practicing metric length unit conversions that include decimals. Specifically, it provides exercises in converting various metric units such as millimeters, meters, decimeters, centimeters, and hectometers to their corresponding metric base or other specified units. The conversions require understanding of scaling metric units up and down, including the use of decimal places to represent more precise values. This practice is instrumental for mastering measurements and aiding in more complex arithmetic involving dimensions and scaling. Each question presents a value in one metric unit with multiple choice answers for the conversion.