Change in the World Price of good Income (170), 60) Price of Related Good (140X, 120Y) EO. (100x, 100Y) Income $2000, P-$10, P,-$10 Elasticity Price Elasticity (always positive) Income Elasticity Cross Price Elasticity 1C (SOX, 300Y) Formula ED = E = ECP 1% %AP IC, Good Y %4Q %AIncome Income $2000, P $10, P, 55 %AQ Good B % AP Good A Terminology Elastic (>1) Inelastic (<1) Normal (>0) Inferior (<0) Substitutes (>0) Complements (<0) The cross price elasticity when the price of Y drops from $10 to $5, using the endpoint method is