O Level Economics: Microeconomic Decision Makers (Cambridge 2281)

Topics 1 and 2 of Cambridge O Level Economics (2281) establish scarcity, opportunity cost and the price mechanism as abstract tools. Topic 3 Microeconomic decision makers puts those tools to work by asking who actually makes economic decisions in a real economy, examined through five decision-maker categories: banks, households, workers, trade unions and firms. Economics at 2281 is not tiered, and content is assessed across Paper 1 (Multiple Choice) and Paper 2 (Structured Questions).

3.1 Money and banking

This sub-topic covers the forms, functions and characteristics of money, and the role and importance of both central banks and commercial banks for government, producers and consumers. A central bank typically oversees the banking system and implements monetary policy on the government’s behalf (a link forward to Topic 4.4); commercial banks are the institutions households and firms actually use to hold deposits, take loans and make payments.

3.2 Households

Households make three interlinked financial decisions: spending, saving and borrowing. The syllabus names three specific influences on these decisions – income, the rate of interest, and confidence – and requires you to be able to explain how each varies both between different households and over time for the same household. Higher confidence about future income, for example, typically increases spending and borrowing and reduces the incentive to save, independent of any change in current income itself.

3.3 Workers

This is one of the largest sub-topics in Topic 3, covering four distinct areas:

• Choice of occupation: wage factors (pay, benefits) and non-wage factors (job security, working conditions, career progression) that influence which job a person chooses.
• Wage determination: demand and supply in the labour market, relative bargaining power, and government policy including the minimum wage. You need to be able to draw and interpret diagrams showing how changes in labour demand and supply affect wages.
• Reasons for differences in earnings: how demand and supply, relative bargaining strength, discrimination and government policy combine to produce earnings gaps between workers who are skilled/unskilled, in the primary/secondary/tertiary sectors, male/female, or in the private/public sector.
• Division of labour and specialisation: the advantages and disadvantages for workers, firms and the economy of breaking production down into specialised tasks.

3.4 Trade unions

You need to define what a trade union is and describe its role in the economy: engaging in collective bargaining over wages, working hours and working conditions, protecting employment, and influencing government policy. The syllabus also asks for the factors that influence how strong a trade union is, and the advantages and disadvantages of trade union activity assessed from three separate viewpoints – workers, firms and government – since the same union action (for example, a successful pay claim) can look like a benefit from one viewpoint and a cost from another.

3.5 Firms

This sub-topic covers how firms are classified and how they grow:

• Classification: by primary/secondary/tertiary sector, by private/public sector, and by relative size. Detailed knowledge of firms’ internal organisational structures is explicitly not required.
• Small firms: their advantages and disadvantages, the challenges they face, and the reasons they continue to exist alongside larger competitors.
• Growth: internal growth (for example, increasing market share through the firm’s own operations) versus external growth (for example, mergers).
• Mergers: the examples, advantages and disadvantages of horizontal (same stage, same industry), vertical (different stage, same industry) and conglomerate (unrelated industries) mergers.
• Economies and diseconomies of scale: how both internal and external economies and diseconomies of scale affect a firm or industry as production scales up.

3.6 Firms and production

Three linked ideas: what drives a firm’s demand for factors of production (demand for the firm’s product, the price of different factors, their availability and their productivity); the difference between labour-intensive and capital-intensive production and why a firm might choose one over the other; and the distinction between production (total output) and productivity (output per unit of input), and what influences each.

3.7 Firms’ costs, revenue and objectives

This sub-topic introduces cost and revenue calculations that recur throughout the rest of the syllabus:

Term	Definition
Total cost (TC)	Fixed cost + variable cost
Fixed cost (FC)	Cost that does not change with output
Variable cost (VC)	Cost that changes directly with output
Average total cost (ATC)	TC ÷ output
Average fixed cost (AFC)	FC ÷ output
Average variable cost (AVC)	VC ÷ output
Total revenue (TR)	Price × quantity sold
Average revenue (AR)	TR ÷ quantity sold

Marginal cost and marginal revenue are explicitly not required at this level. You need to be able to calculate each of the terms above from given data, and to draw and interpret diagrams showing how changes in output affect costs of production. The sub-topic closes with firms’ possible objectives – survival, social welfare, profit maximisation and growth – which are not mutually exclusive and may change depending on a firm’s circumstances (a struggling firm may prioritise survival; an established firm may prioritise growth).

3.8 Market structure

The final sub-topic contrasts two ends of a spectrum: competitive markets, where a high number of firms affects price, quality, choice and profit in ways favourable to consumers, and monopoly markets, covering the characteristics, advantages and disadvantages of a market dominated by a single firm. The syllabus is explicit that the full theory of perfect and imperfect competition, and any accompanying diagrams, are not required for either – keep your answers to the named characteristics and effects rather than importing diagram-based analysis from a higher-level course.

How to approach it

Because Topic 3 is organised around five decision-maker categories rather than one continuous argument, the most efficient revision approach is to build a short answer to “what decision does this maker face, and what factors influence it?” for each of the five in turn – banks (how to support the economy), households (spend, save or borrow), workers (which job, and how hard to bargain for pay), trade unions (how to represent workers’ interests) and firms (how to grow, what to produce, and by what method). The costs and revenue formulas in 3.7 are the most calculation-heavy content in this topic and are frequently tested numerically on Paper 1’s multiple-choice questions, so practise moving between raw figures and the TC/ATC/FC/VC/AFC/AVC/TR/AR labels fluently rather than only recognising the definitions in words.

Official syllabus

Cambridge International, Cambridge O Level Economics (2281) syllabus for examination in 2026 (Version 2, published December 2025): official syllabus PDF, Subject content, section 3 “Microeconomic decision makers”. Verified 2026-09-02.