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A complete principles of microeconomics course, built from the 20 chapters of OpenStax Principles of Microeconomics 3e plus its appendix on graphs. It starts with scarcity, opportunity cost and the production possibilities frontier, then builds the supply and demand model, price controls, consumer and producer surplus, and elasticity. The middle of the course covers consumer choice, production and cost curves, and the four market structures: perfect competition, monopoly, monopolistic competition and oligopoly, with antitrust policy. The last units apply the tools to externalities and the environment, public goods, labor markets, poverty and inequality, information and insurance, financial markets, public choice, and international trade. Every calculation (midpoint elasticity, cost tables, MR = MC, surplus, comparative advantage, concentration ratios) is a typed card whose answer was recomputed by script. Cards are text only: every graph is described as a scenario, and dated figures carry their year.
Copied straight from the course. In the app, each wrong option also gets its own explanation.
Card 1A firm raises its price from $4 to $5, and quantity sold falls from 1,000 to 900. What happens to its total revenue? Give the change to the nearest dollar.
It rises by $500. TR goes from $4 x 1,000 = $4,000 to $5 x 900 = $4,500, a rise of $500. Demand is inelastic here (about 0.47).
Card 2At a firm's current output, marginal revenue is $10 and marginal cost is $7. What change would raise its profit?
Increase its output. When MR > MC, each extra unit adds more to revenue than to cost, so expanding output raises profit until MR = MC.
Card 3A good is nonexcludable but rival. How do economists classify it?
A common resource. Ocean fish are an example: no one can easily be stopped from fishing, but each fish caught is one fewer for others.
Yes. Create a free Encodr account and all 20 units and 1,194 cards are yours to study, with spaced repetition scheduling your reviews.
OpenStax Principles of Microeconomics 3e (all 20 chapters and the graphs appendix, CC BY-NC-SA) plus standard introductory definitions. The cards are rewritten, not copied.
Scarcity and choice, supply and demand, labor and financial markets, elasticity, consumer choice, production and costs, perfect competition, monopoly, monopolistic competition and oligopoly, antitrust, externalities, public goods, labor markets, poverty and inequality, information and insurance, financial markets, public choice, and international trade.
Yes. Midpoint elasticity, total revenue, cost tables, MR = MC, profit, surplus, comparative advantage and concentration ratios are typed practice cards, and every answer was recomputed by script.
No. Cards are text only, so every supply and demand, cost-curve and market-structure graph is described as a scenario in words, and the graph rules are stated in each chapter's notes card.