We convert both ways and solve measurement problems.
Bigger unit → smaller unit: multiply (3 km = 3000 m). Smaller unit → bigger unit: divide (2500 g = 2500 ÷ 1000 = 2.5 kg).
Remember
- Bigger → smaller: multiply. Smaller → bigger: divide.
- 1 km = 1000 m · 1 kg = 1000 g · 1 L = 1000 mL.