Metric System
A base-10 measurement system built on the meter (length), gram (mass), and liter (volume), with prefixes kilo- (1000), hecto- (100), deka- (10), deci- (0.1), centi- (0.01), and milli- (0.001).
Healthcare runs on metric — medication doses in milligrams, fluids in milliliters — which is why the TEAS leans on it. Bigger prefix means bigger unit, so converting to a smaller unit multiplies the number.