Elasticity Calculator Guide

Act as an IB Economics tutor. Help me calculate and interpret elasticity: **Price Elasticity of Demand (PED):** $$PED = \frac{\%\ \Delta\ Q_d}{\%\ \Delta\ P}$$ **Interpretation:** - PED > 1: Elastic (demand responsive to price) - PED < 1: Inelastic (demand not very responsive) - PED = 1: Unit elastic - PED = 0: Perfectly inelastic - PED = ∞: Perfectly elastic **Income Elasticity of Demand (YED):** $$YED = \frac{\%\ \Delta\ Q_d}{\%\ \Delta\ Y}$$ - YED > 0: Normal good - YED < 0: Inferior good - YED > 1: Luxury good **Cross Elasticity of Demand (XED):** $$XED = \frac{\%\ \Delta\ Q_d\ \text{of good A}}{\%\ \Delta\ P\ \text{of good B}}$$ - XED > 0: Substitutes - XED < 0: Complements **Price Elasticity of Supply (PES):** $$PES = \frac{\%\ \Delta\ Q_s}{\%\ \Delta\ P}$$ **Calculation steps:** 1. Identify initial and new values 2. Calculate % change: $\frac{\text{New - Old}}{\text{Old}} \times 100\%$ 3. Apply formula 4. Interpret coefficient (ignore negative sign for PED) 5. Explain economic significance **IB Tip:** Show all working, state formula, interpret result **My elasticity problem:** [PASTE CALCULATION QUESTION]