Economics Questions Answered, One Page Each

A commodity such as wheat or a farmers market selling identical produce is close to perfect competition, and a local water utility or a patented drug is close to a monopoly. Place a real firm by counting sellers, checking whether the product is identical, and measuring entry barriers.

A monopoly is a single firm with no competitors, while a cartel is a group of competing firms that agree to act like one firm by fixing prices or output. That agreement is the whole difference, and it is also why cartels tend to fall apart as individual members cheat on it.

Find a Nash equilibrium by checking every cell of a payoff matrix: if either player would rather switch given what the other player picked, that cell is not the equilibrium. A Nash equilibrium is a combination of choices where no player can do better by changing only their own choice.

Find the quantity where marginal revenue equals marginal cost, then compare price to average total cost there: price above ATC means profit, equal means break even, below means a loss. A flat demand curve marks a price taking firm; a downward sloping one marks a firm with market power.

A monopoly produces less output and charges a higher price than a perfectly competitive market serving the same demand, because the monopolist sets marginal revenue equal to marginal cost while price sits above marginal revenue; the surplus lost on the units not produced is deadweight loss.

A production possibilities curve rests on four assumptions: two goods, a fixed quantity of resources, fixed technology, and full and efficient use of those resources, plus a fixed time period; each one strips out real-world detail so one graph can show the tradeoff between two outputs.

The current account records trade in goods and services, income, and transfers, while the capital and financial account records purchases and sales of assets; money entering a country is a credit, money leaving is a debit, and the two accounts sum to roughly zero.

Saving, taxes, and imports are the three leakages that pull money out of the circular flow. Investment, government spending, and exports are the matching injections that put it back in, and equilibrium requires the two totals to be equal.

That point is equilibrium, specifically the equilibrium level of real GDP in the circular flow model: the output level where saving plus taxes plus imports (total leakages) equals investment plus government spending plus exports (total injections).

Households sell labor in the resource market, also called the factor market, where households supply labor, land, capital, and entrepreneurship to firms in exchange for wages, rent, interest, and profit.

Money is the payment for the goods and factors moving the other way. Households pay firms for output in the product market, and firms pay households for labor and other inputs in the factor market, so every real flow has a matching money flow running backward.

Yes, through trade. A country can never produce past its own production possibilities curve, but specializing in the good where it holds a comparative advantage and trading for the other good lets it consume a bundle that sits outside that curve.

A market economy relies only on prices and private decisions to answer what, how, and for whom to produce, while a mixed economy keeps that market core but adds government action such as public goods, regulation, and transfers. Every real economy in operation today is mixed to some degree.

The three basic economic questions are what to produce, how to produce it, and for whom to produce it. Every economy, whether market, command, or mixed, has to answer all three because scarce resources can never satisfy every want, so someone has to choose.

A production possibilities curve shows three things: scarcity, since it sits on a fixed frontier for two goods; opportunity cost, read as the slope between two points; and efficiency, since only points on the curve use every resource fully. A shifting curve adds growth.

A point inside the production possibilities curve represents an inefficient use of resources: the economy is producing less of both goods than it could, usually because of unemployment or idle capital. A point on the curve is efficient; a point outside it is currently unattainable.

PPC stands for production possibilities curve, also called the production possibilities frontier. It is the graph showing the maximum combinations of two goods an economy can produce when every resource is fully and efficiently employed.

The circular flow model shows how households and firms exchange goods, services, resources, and money. The fuller version adds the government and the rest of the world, moving through the product market and the factor market.

A change in the quantity or quality of resources, or a change in technology, shifts the whole production possibilities curve: outward for economic growth, inward for a loss of resources. A PPC showing economic growth shifts outward, away from the origin.

The producer with the lower opportunity cost for that good has the comparative advantage, not the one who can make more of it. To answer the question you need each producer's opportunity cost, not their output level alone.