💰 Opportunity Cost
Definition: Opportunity cost is the next best alternative forgone when a choice is made. It's the value of the thing you give up when you choose one option over another.
Why is this so important?
Because resources are scarce, every decision has an opportunity cost. This applies to everyone:
- Individuals — choosing to spend €50 on a concert means you can't spend that €50 on clothes
- Firms — investing in new machinery means those funds can't be used for marketing
- Governments — spending on defence means less available for healthcare or education
Example: You have 2 hours of free time. You can study, play football, or watch TV. If you choose to study, and football was your next best option, the opportunity cost is the football game you missed — NOT the TV show.
It's the NEXT BEST alternative — not ALL the alternatives. Only the single best option you gave up! 🎯
📊 Opportunity Cost on the PPC
The PPC is the best way to SEE opportunity cost in action. Moving along the curve, producing more of one good means producing less of the other.
- Moving from one point to another on the PPC shows the trade-off clearly
- The amount of Good B you give up to get more Good A = the opportunity cost of Good A
- A curved (concave) PPC means increasing opportunity cost — each extra unit costs more and more to produce
An economy produces wheat and cars. Moving from point A (100 wheat, 20 cars) to point B (80 wheat, 30 cars), the opportunity cost of 10 extra cars = 20 units of wheat forgone.
In exams, always state the opportunity cost clearly: 'The opportunity cost of producing 10 more cars is 20 units of wheat forgone.' Be specific with numbers if the question gives data!
See how examiners mark answers
Access past paper questions with model answers. Learn exactly what earns marks and what doesn't.
Try Exam Vault Free7-day free trial • No card required
⚖️ Trade-offs Everywhere
A trade-off means giving up some of one thing to get more of another. Trade-offs are at the heart of every economic decision.
- Consumers trade off between different goods when spending their limited income
- Firms trade off between profit today and investment for the future
- Governments trade off between equity (fairness) and efficiency, or between spending on different public services
Example: A government faces a trade-off between military spending and education spending. More tanks = fewer teachers. The PPC shows this perfectly.
Key government trade-offs
Governments face some especially important trade-offs that come up a lot in IB Economics:
- Equity vs efficiency — making the economy more fair might reduce total output
- Economic growth vs environmental sustainability — more production can damage the planet
- Low inflation vs low unemployment — policies that reduce one may increase the other
- Short-run benefits vs long-run costs — spending now may mean debt later
These government trade-offs are examined in detail in Units 2 and 3. Understanding them early gives you a head start!