2.4 Elasticities of Supply and Demand Elasticity-Percentage change in one variable resulting from a 1-percent increase in another. Elasticities describe the responsiveness of supply and demand to changes in price,income,or other variables.2.4 Elasticities of Supply and Demand ❑ Elasticity-Percentage change in one variable resulting from a 1-percent increase in another. ❑ Elasticities describe the responsiveness of supply and demand to changes in price, income, or other variables