Ib Economics Hl Formula Booklet Repack | !!top!!

Always negative due to the law of demand (ignore the sign for interpretation). Key Ranges: (Elastic), (Inelastic), (Unit Elastic). Cross-Price Elasticity of Demand (XED)

| Concept | Official Formula | Repack Strategy (The "Cheat Code") | | :--- | :--- | :--- | | | (%ΔQd)/(%ΔP) | Remember: Always report absolute value (drop -). | | YED | (%ΔQd)/(%ΔY) | Sign matters: + = Normal good; - = Inferior. | | XED | (%ΔQd Good A)/(%ΔP Good B) | + = Substitutes; - = Complements. | | PES | (%ΔQs)/(%ΔP) | Flows from zero to infinity. | | Tax Revenue | Tax per unit × Quantity after tax | Draw the wedge. Area of rectangle under DWL. | | Consumer Surplus (CS) | ½ × Base × Height (demand curve to price) | After tax, CS shrinks to the triangle left of Qty new. | | Producer Surplus (PS) | ½ × Base × Height (price to supply curve) | After tax, PS shrinks. | | DWL (Tax) | ½ × (Tax per unit) × (ΔQuantity) | The deadweight loss triangle. | | Price Ceiling Shortage | Qty demanded – Qty supplied (at ceiling price) | Calculate using the linear functions. | ib economics hl formula booklet repack

The official booklet scatters the expenditure approach (GDP = C+I+G+(X-M)), the multiplier, and the Phillips curve. A repack forces them onto a single spread. Always negative due to the law of demand

Development Economics

Identifies if two goods are substitutes (positive result) or complements (negative result). | | YED | (%ΔQd)/(%ΔY) | Sign matters:

XED=%ΔQd of Good X%ΔP of Good YXED equals the fraction with numerator % cap delta cap Q sub d of Good X and denominator % cap delta cap P of Good Y end-fraction (Positive): Substitutes (e.g., Pepsi and Coca-Cola) (Negative): Complements (e.g., Printers and Ink cartridges) : Unrelated goods Income Elasticity of Demand (YED) Formula: