| In economics, supply and demand describes market relations between prospective sellers and buyers of a good. The supply and demand model determines price and quantity sold in the market. The model is fundamental in microeconomic analysis of buyers and sellers and of their interactions in a market. It is used as a point of departure for other economic models and theories. The model predicts that in a competitive market, price will function to equalize the quantity demanded by consumers and the quantity supplied by producers, resulting in an economic equilibrium of price and quantity. The model incorporates other factors changing such equilibrium as reflected in a shift of demand or supply.
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