Cambridge IGCSE Economics 0455: Frequent mistakes

Cambridge Principal Examiner Reports for Economics 0455 highlight recurring weaknesses in data use, diagrams, elasticity and evaluation. Addressing these improves your grade.

Data interpretation and source material

Overlooking source data

Candidates often ignore data provided when instructed to use it. They answer from general knowledge instead of the specific source.

Fix: Read all sources. Quote or refer to figures. “According to the table…”, “The data shows…”

Superficial analysis

Surface-level analysis instead of thorough identification of trends, patterns and implications. Key trends in the data are missed.

Fix: Describe trends. Identify patterns. Explain what they mean or imply.

Elasticity concepts

Confusion with PED and PES

Confusion between price elasticity of demand (PED) and price elasticity of supply (PES). Misunderstanding what “elastic” means (responsiveness to price change).

Fix: PED = % change in Qd ÷ % change in P. Elastic > 1; inelastic < 1. PES = % change in Qs ÷ % change in P.

Wrong application

Using elasticity as “relationship between price and quantity” instead of proportionate responsiveness to price change.

Fix: Elasticity = responsiveness. PED measures how much quantity demanded changes when price changes.

Diagram drawing and interpretation

Drawing errors

Challenges drawing accurate supply and demand diagrams. Wrong axes; missing labels; incorrect shifts.

Fix: Label axes (P, Q). Label curves (S, D). Show shifts clearly. Mark new equilibrium.

Interpretation errors

Correct diagram but wrong interpretation. Not explaining what the diagram shows or linking it to the question.

Fix: After drawing, explain: “This shows…”, “Equilibrium shifts from… to…”, “Price increases because…”

Extended responses and evaluation

Underdeveloped evaluation

Extended responses often lack sufficient evaluation. Candidates list points without judging their relative importance or concluding.

Fix: Give both sides. Weigh up. Reach a conclusion. “On balance…”, “However…”, “The most important factor is…”

Inadequate development

Arguments not developed enough. Single sentence per point instead of explanation and examples.

Fix: Explain each point. Use examples. Link to the question context.

Terminology and multiple choice

Misunderstanding economic terms

Fundamental confusion with key terms—e.g. average fixed cost vs. average total cost; supply-side economics; free market characteristics.

Fix: Learn precise definitions. Average fixed cost = TFC ÷ Q. Average total cost = TC ÷ Q.

Multiple choice errors

Common difficulty with: average fixed costs; supply-side economics; infant mortality rates; free market characteristics. Reading the stem carefully.

Fix: Read all options. Eliminate wrong answers. Check “not” or “except” in the stem.

How Tutopiya helps

Tutopiya supports Cambridge IGCSE Economics. Explore IGCSE resources or book a free trial.

---

Based on Cambridge IGCSE Economics 0455 Principal Examiner Reports (2020–2023).