The higher the price of an assigned textbook, the less the quantity demanded of assigned textbooks will be, ceteris paribus, and the more likely students will seek out an alternative to the assigned textbook. In other words, a product or service will sell a higher quantity and be more in demand if the price is lowered. If a product or service has a price that becomes too high, the quantity will not be in demand as much and it will sell less. One thing to keep in mind is equality, the products or services being sold must be equal in everything but price for the law of demand to remain true.
