M4.5.5 For the adult
Changing units of area and volume
How many square centimetres are in one square metre?
What this chapter teaches
If lengths change by a factor k, areas change by k² and volumes by k³. So 1 m² is 10 000 cm² and 1 m³ is 1 000 000 cm³. A litre is 1 000 cm³, a millilitre is 1 cm³, and 1 m³ is 1 000 litres.
Three questions to ask
There is no one right wording. Listen for the idea.
- Why is there no way that 1 m² could be 100 cm²?
- How can you show that a litre is 1 000 cm³ with a box?
- How many litres are in a cubic metre, and how do you know?
After the chapter, the learner can
- Change between cm² and m², and between cm³ and m³
- Change between cm³, litres and m³
What they copy into their notebook
1 m² = 10 000 cm². 1 m³ = 1 000 000 cm³. 1 litre = 1 000 cm³. 1 ml = 1 cm³. 1 m³ = 1 000 litres. Small unit to big unit: divide.