@coursesforcrammers: Screwed for your Microeconomics Midterm? This is the underlying principle of ELASTICITY that you need to understand. Elasticity, at its core, is simply PERCENT CHANGE in QUANTITY vs. PRICE. And whenever Quantity changes by a LARGER ABSOLUTE % than Price... Consumers/Producers (whether we're working with Demand/Supply) are MORE REACTIVE to changes in price. And our Demand/Supply will be ELASTIC. On the flip side... Whenever Quantity changes by a SMALLER ABSOLUTE % than Price... Consumers/Producers are LESS REACTIVE to changes in price. And our Demand/Supply will be INELASTIC. What if Quantity and Price change by the same absolute %? Then our Demand/Supply will be UNIT ELASTIC. Want to get some practice in and see where you stand? Take my FREE MICROECONOMICS PRACTICE EXAM (link in bio) with 25 of the most typical types of questions professors put on their exams. Get instant results, and a unit-by-unit breakdown so you can see where to focus your studies.