Markets work differently depending on how many sellers offer the same good or service. When many sellers compete, customers can compare prices, quality, and features before buying. When one seller controls the market, customers have fewer choices and less power.
Understanding competition and monopoly helps students make smarter personal finance choices and understand why some prices feel fair while others feel high.
Key Facts
- More sellers usually increase competition, which tends to lower prices and improve choices for consumers.
- A monopoly is a market with one dominant seller and few or no close substitutes.
- In competitive markets, firms often act as price takers because customers can switch to another seller.
- In monopoly markets, the seller has more price-setting power because customers have fewer alternatives.
- Profit = total revenue - total cost.
- Market share = firm's sales / total market sales x 100%.
Vocabulary
- Competition
- Competition is the rivalry among sellers to attract customers by offering better prices, quality, service, or features.
- Monopoly
- A monopoly is a market structure in which one seller controls most or all of the supply of a product with few close substitutes.
- Market share
- Market share is the percentage of total sales in a market that belongs to one firm.
- Consumer power
- Consumer power is the ability of buyers to influence sellers through their choices, spending, and willingness to switch.
- Barrier to entry
- A barrier to entry is anything that makes it difficult for new firms to enter a market, such as high startup costs, patents, or control of key resources.
Common Mistakes to Avoid
- Assuming a monopoly always charges any price it wants is wrong because even monopolies face limits from consumer budgets, demand, substitutes, and regulation.
- Thinking competition only affects price is wrong because sellers also compete through quality, convenience, customer service, design, and innovation.
- Counting brands instead of actual sellers is wrong because several brands may be owned by the same company, which can reduce true competition.
- Ignoring barriers to entry is wrong because a market may look profitable, but new sellers cannot easily compete if startup costs, patents, or network effects are too strong.
Practice Questions
- 1 A town has 5 pizza shops. Their weekly sales are 200, 250, 150, 300, and 100 pizzas. What is the market share of the shop that sells 300 pizzas?
- 2 A company sells 8,000 phone plans in a city where 10,000 phone plans are sold in total each month. Calculate the company’s market share. Does this suggest strong market power?
- 3 Explain how a student buying school supplies might experience different prices, choices, and service in a competitive market compared with a monopoly market.