The market determines the price of products by two general rules: the laws of demand and supply. For example, how many tomatoes will consumers buy at various prices? This is demand. The law of demand states that consumers (buyers) usually buy more of a product at a lower price. How many tomatoes will the sellers product at various prices? This is supply. The law of supply states that producers usually supply more of a product at a higher price. Consumers, of course, want a low price, but producers need to make a profit .The actions of consumers and producers determine the price.