First of all, understand the meaning of a perfectly competitive market. The so-called perfect competitive market means that commodity prices are completely determined by market supply and demand. In this way, the price when the market supply and demand are equal is the equilibrium price P. In a perfectly competitive market, the equilibrium price is constant (for example, when the market supply and demand change, it is no longer supply = demand, if the demand increases, then supply.

After understanding the perfectly competitive market and the fact that P determined by it is constant, it is easy to analyze that the average income AR= marginal income MR. P is the price, and it is also the profit of each commodity sold by the manufacturer. If p remains the same, then no matter how many goods the manufacturer sells, the average profit is p. For example, if a manufacturer sells n kinds of goods, the average profit is AR = NP/N = P, and the marginal revenue MR refers to the revenue of each unit of goods sold by the manufacturer, and P remains unchanged, so the revenue of each unit of goods sold by the manufacturer is always P, which will not change, that is, Mr = P.

So there is AR = MR = P. For a simple example, suppose that the product price of a manufacturer is P= 10 yuan and a * * production 10, then the average income is AR =10/10 yuan.