Marginal Revenue

income of a business from sales of every additional product, MR (Economics)

In microeconomics, Marginal Revenue (MR) is the extra revenue that an additional unit of product will bring to a firm. It can also be described as the change in total revenue/change in number of units sold. More formally, marginal revenue is equal to the change in total revenue over the change in quantity when the change in quantity is equal to one unit (or the change in output in the bracket where the change in revenue has occurred)This can also be represented as a derivative. (Total revenue) = (Price) times (Quantity) or . Thus, by the product rule: .
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The change in total revenue as a result of producing one additional unit of output.