Final answer:
The economic system rewarding firms for meeting consumer demands is called a market economy, where prices are established by supply and demand.
Step-by-step explanation:
The economic system that rewards firms for their ability to perceive and serve the needs and demand of consumers is known as a market economy. In a market economy, the prices of goods and services are determined largely by supply and demand in the marketplace. This system relies on the mechanism of markets, where no single governing body dictates production or distribution. Instead, consumers influence what is produced and for whom by their purchasing choices, and businesses respond to those signals by competing to meet those needs in the hopes of achieving profits.