The Demand Curve for Used TextbooksWith only five potential consumers in this market, the demand curve is step-shaped. Each step represents one consumer, and its height indicates that consumer’s willingness to pay—the maximum price at which each will buy a used textbook—as indicated in the table. Aleisha has the highest willingness to pay at $59, Brad has the next highest at $45, and so on down to Edwina with the lowest willingness to pay at $10. At a price of $59, the quantity demanded is one (by Aleisha); at a price of $45, the quantity demanded is two (by Aleisha and Brad); and so on until you reach a price of $10, at which all five students are willing to purchase a book.