This text is designed to explain what a "repack" is, why it is useful, and provides a structured breakdown of the essential content students need to master.
The Ultimate Guide to the IB Economics HL Formula Booklet: The "Repack" For students navigating the rigorous landscape of the International Baccalaureate (IB) Economics Higher Level (HL) course, the Data Response Paper (Paper 3) is a unique challenge. Unlike Standard Level, HL students must grapple with quantitative tools—calculating elasticities, costs, revenues, and trade indices. While the IB Organization provides an official formula booklet, it is often a dense, sterile document that can be difficult to navigate under exam pressure. This is where the concept of a "Repack" comes in. What is a "Formula Booklet Repack"? A "Repack" is not a new official document. It is a study strategy where the raw formulas are reorganized, contextualized, and annotated for practical use. Think of it as translating the language of mathematics into the language of exam technique. Instead of a list of symbols, a repack organizes formulas by concept , provides memory aids , and highlights common pitfalls . Below is the definitive "Repack" of the IB Economics HL quantitative syllabus.
Section 1: Microeconomics – The Mechanics of Markets 1. Elasticities: Measuring Responsiveness The most common calculations in Paper 3 involve determining how quantity and price interact. A repack organizes these not just by formula, but by interpretation. A. Price Elasticity of Demand (PED)
Formula: $PED = \frac{% \Delta Q_d}{% \Delta P}$ The "Repack" Interpretation: ib economics hl formula booklet repack
Ignore the negative sign in your final answer (demand curves slope down). PED > 1: Elastic (Responsive). PED < 1: Inelastic (Unresponsive). PED = 1: Unit Elastic.
B. Cross Price Elasticity of Demand (XED)
Formula: $XED = \frac{% \Delta Q_{good A}}{% \Delta P_{good B}}$ The "Repack" Interpretation: This text is designed to explain what a
Positive (+): Substitute goods (Coke and Pepsi). Negative (-): Complementary goods (Cars and Petrol).
C. Income Elasticity of Demand (YED)
Formula: $YED = \frac{% \Delta Q_d}{% \Delta Y}$ (Where $Y$ = Income) The "Repack" Interpretation: While the IB Organization provides an official formula
Positive (+): Normal good (Income up, demand up).
$0 < YED < 1$: Necessity. $YED > 1$: Luxury.