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M04.L03 — Market Equilibrium: Supply, Demand, and Price

Module: Module 04 — Supply and Market Equilibrium Lesson: L03 of 06 Duration: ~30 minutes Level: Introductory Provenance: OpenStax Principles of Microeconomics 3e | MIT OCW 14.01 Principles of Microeconomics

Learning Objective

Key Diagram

Figure 2: Supply and Demand. The equilibrium price P* and quantity Q* occur at the intersection of the supply and demand curves.
Figure 2: Supply and Demand. The equilibrium price P and quantity Q* occur at the intersection of the supply and demand curves.*

Determine equilibrium price and quantity using supply and demand curves

Finding Equilibrium

Market equilibrium occurs where quantity supplied equals quantity demanded (Qd = Qs). At this intersection point: - There is no tendency for price to change - The market "clears" with no surplus or shortage - Both buyers and sellers are satisfied

In Australia's housing market, equilibrium prices emerge from the interaction of: - Supply: Available properties, construction costs - Demand: Population growth, interest rates, investor activity

Worked Example

Sydney Apartment Market

  1. Demand function: Qd = 500,000 - 2,000P
  2. Supply function: Qs = 100,000 + 3,000P
  3. Set Qd = Qs → 500,000 - 2,000P = 100,000 + 3,000P
  4. Solve: 400,000 = 5,000P → P* = $80,000 per apartment
  5. Q* = 100,000 + 3,000(80) = 340,000 apartments

Common Misconception

"Equilibrium means equal numbers of buyers and sellers"

Equilibrium means quantities supplied and demanded are equal at a given price, not that the number of participants is equal.

Key Takeaways

  • Equilibrium is the price-quantity combination where markets clear
  • Graphical analysis shows the intersection point
  • Algebraic solutions provide precise values
  • Australian housing demonstrates real-world equilibrium dynamics

Practice

  1. If demand increases while supply stays constant, what happens to equilibrium?
  2. How would higher construction costs affect Sydney's apartment equilibrium?
  3. Why might equilibrium take time to establish in real markets?

Further Resources

Provenance: OpenStax Principles of Microeconomics 3e | MIT OCW 14.01 Principles of Microeconomics