Multiplication
Multiplication combines quantities. In EPSO, you multiply values by weights, populations by per-capita figures, or rates by bases.
Practice This ConceptUnderstanding Multiplication
Multiplication is repeated addition. In EPSO, it appears in weighted averages (value x weight), per-capita to total conversions (rate x population), and compound growth. The key skill is identifying which two numbers to multiply.
Formula
$result = A \times B$
Key Rules
- Order does not matter: A x B = B x A
- Multiplying by less than 1 makes result smaller
- Multiplying by more than 1 makes result bigger
- To convert per-capita to total: multiply by population
Examples in Action
1
4.5 x 67
=
301.5
CO2 per capita x population = total for France
2
7.3 x 83
=
605.9
CO2 per capita x population = total for Germany
3
0.15 x 800
=
120
15% of 800
Common Errors
- Multiplying when you should divide (or vice versa)
- Using the wrong weight or population
- Forgetting to multiply ALL parts in weighted sums
Pro Tip
When you see per-capita data alongside population, you WILL need to multiply them together.