Multiply or divide by 10, 100 or 1,000
You learn to convert length, capacity and mass: know how many small units make one big unit, then multiply or divide.
How to work it out
- Know the facts: 1 km = 1,000 m, 1 m = 100 cm, 1 cm = 10 mm, 1 kg = 1,000 g and 1 l = 1,000 ml.
- If you go to a smaller unit, multiply by the fact.
- If you go to a bigger unit, divide by the fact.
3 m = ? cm
- 1 m = 100 cm.
- You go to the smaller unit, so multiply by 100: 3 × 100 = 300.
- It is 300 cm.
More examples
2 l = ? ml
- 1 l = 1,000 ml.
- Multiply by 1,000: 2 × 1,000 = 2,000.
- It is 2,000 ml.
2 kg = ? g
- 1 kg = 1,000 g.
- Multiply by 1,000: 2 × 1,000 = 2,000.
- It is 2,000 g.
1,500 m = ? km
- 1 km = 1,000 m.
- You go to the bigger unit, so divide by 1,000: 1,500 ÷ 1,000 = 1.5.
- It is 1.5 km.