Supply and demand

In this episode, we explore the engine of the market economy: supply and demand. These are the two fundamental forces that interact to determine the price and quantity of nearly everything you buy. We'll break down the 'Law of Demand,' which explains consumer behavior, and the 'Law of Supply,' which governs producer behavior. You'll learn how the interaction of these two forces creates an 'equilibrium' price where buyers and sellers agree. We will also investigate what happens when prices are out of balance, leading to shortages or surpluses, and see how the market naturally pushes back toward a stable point.

Check your understanding

These are the same multiple-choice questions you will see in the Quiz section after you listen to the episode. Use them here to preview or review the answers.

The Law of Demand states that, all other factors being equal, as the price of a good or service falls, what happens?

  1. The quantity demanded increases.
  2. The quantity demanded decreases.
  3. The quantity supplied increases.
  4. The supply remains constant.
  5. The demand for substitutes increases.

What is the relationship described by the Law of Supply?

  1. As price increases, quantity supplied decreases.
  2. As price decreases, quantity supplied increases.
  3. As price increases, quantity supplied increases.
  4. As price increases, demand decreases.
  5. Producers will supply whatever amount consumers demand.

What is the term for the point at which the quantity consumers want to buy is exactly equal to the quantity producers want to sell?

  1. A surplus
  2. A shortage
  3. The price ceiling
  4. Equilibrium
  5. The demand point

If the current price of a product is set above the equilibrium price, what will be the result?

  1. A shortage, because quantity demanded will exceed quantity supplied.
  2. A surplus, because quantity supplied will exceed quantity demanded.
  3. The market will be in equilibrium.
  4. The demand for the product will increase.
  5. Producers will stop making the product.

Imagine a very popular new video game is released at a very low price. Long lines form and the game sells out immediately. This situation is an example of what?

  1. A surplus
  2. Market equilibrium
  3. Excess supply
  4. A shortage
  5. The Law of Supply

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