Between two points on a demand curve, price falls from $70 to $60 and quantity demanded rises from 2,800 to 3,000. Using the midpoint method, what is the price elasticity of demand over this interval?

1. Percentage change in quantity: (3,000 minus 2,800) divided by the average of 3,000 and 2,800, which is 2,900, times 100. 2. That gives 200 divided by 2,900, times 100, which is about 6.9 percent. 3. Percentage change in price: (60 minus 70) divided by the average of 60 and 70, which is 65, times 100. 4. That gives negative 10 divided by 65, times 100, which is about negative 15.4 percent. 5. Price elasticity of demand equals 6.9 divided by 15.4, read as a positive number, which is about 0.45. 6. Since 0.45 is below one, demand is inelastic over this interval, not elastic. 7. Option A's 1.47 belongs to a different, higher-price pair of points on the same demand curve. 8. Option C's 3.53 is a price elasticity of supply figure from the apartment rental example, not this demand calculation. 9. Option D's exactly 1.00 would require the two percentage changes to be identical, which they are not here. _Source: OpenStax Principles of Microeconomics for AP Courses (CC BY 4.0), Ch 5 "Elasticity", section 5.1 | Price Elasticity of Demand and Price Elasticity of Supply_