Marginal revenue in the context of "Perfect competition"

In microeconomics, a monopoly price is set by a monopoly. A monopoly occurs when a firm lacks any viable competition and is the sole producer of the industry's product. Because a monopoly faces no competition, it has absolute market power and can set a price above the firm's marginal cost.

The monopoly ensures a monopoly price exists when it establishes the quantity of the product. As the sole supplier of the product within the market, its sales establish the entire industry's supply within the market, and the monopoly's production and sales decisions can establish a single price for the industry without any influence from competing firms. The monopoly always considers the demand for its product as it considers what price is appropriate, such that it chooses a production supply and price combination that ensures a maximum economic profit, which is determined by ensuring that the marginal cost (determined by the firm's technical limitations that form its cost structure) is the same as the marginal revenue (MR) (as determined by the impact a change in the price of the product will impact the quantity demanded) at the quantity it decides to sell. The marginal revenue is solely determined by the demand for the product within the industry and is the change in revenue that will occur by lowering the price just enough to ensure a single additional unit is sold. The marginal revenue is positive, but it is lower than its associated price because lowering the price will increase the demand for its product and increase the firm's sales revenue, and lower the price paid by those who are willing to buy the product at the higher price, which ensures a lower sales revenue on the product sales than those willing to pay the higher price.