According to the optimal output rule,profits are maximized when firms produce where the difference between marginal revenue and marginal cost is the largest.

Optimal Output Rule

The principle that profit is maximized by producing the quantity of output at which the marginal revenue of the last unit produced is equal to its marginal cost.

Marginal Revenue

The additional income earned by a company from selling one more unit of a good or service, reflecting the benefit of increased production.

Marginal Cost

The boost in expense for crafting one more unit of a product or service.