Ch. 4 - ElasticityWorksheetSee all chapters
All Chapters
Ch. 1 - Introduction to Microeconomics
Ch. 2 - Introductory Economic Models
Ch. 3 - Supply and Demand
Ch. 4 - Elasticity
Ch. 5 - Consumer and Producer Surplus; Price Ceilings and Floors
Ch. 6 - Introduction to Taxes and Subsidies
Ch. 7 - Externalities
Ch. 8 - The Types of Goods
Ch. 9 - International Trade
Ch. 10 - The Costs of Production
Ch. 11 - Perfect Competition
Ch. 12 - Monopoly
Ch. 13 - Monopolistic Competition
Ch. 14 - Oligopoly
Ch. 15 - Markets for the Factors of Production
Ch. 16 - Income Inequality and Poverty
Ch. 17 - Asymmetric Information, Voting, and Public Choice
Ch. 18 - Consumer Choice and Behavioral Economics
To solve our different answer dilemma, we use the midpoint method.

Concept #1: The Midpoint Method

Practice: The price of widgets is currently $44 with a quantity demanded of 200,000 units. If the price decreases to $36, the quantity demanded increases 280,000. Using the midpoint method, what is the price elasticity of demand? Is demand elastic or inelastic?

Practice: The price of a good rises from $8 to $12, and the quantity demanded falls from 110 to 90 units. Using the midpoint method, what is the price elasticity of demand?

Practice: Assume that the price elasticity of demand for cigarettes is 0.4. If a pack of cigarettes currently costs $6 and the government aims to decrease smoking by 20 percent, by how much should it increase the price?