Final answer:
Marginal revenue for a firm, especially a monopolist, is calculated by dividing the change in total revenue by the change in quantity sold. For perfectly competitive firms, marginal revenue equals the market price. For monopolists, the marginal revenue curve lies beneath the demand curve due to the downward-sloping demand they encounter.
Step-by-step explanation:
The formula for calculating marginal revenue in the context of a private seller or a firm, particularly one with market power like a monopolist, is derived by calculating the change in total revenue that results from selling an additional unit of a product, and dividing it by the change in quantity sold. To find the deficit figure, if any, one would consider the discrepancy between marginal revenue and marginal cost, but the question seems to focus solely on how marginal revenue is determined based on a demand equation.
For a perfectly competitive firm, the marginal revenue would equal the market price, as the demand curve they face is perfectly elastic. This means that each additional unit sold adds exactly the market price to the total revenue. However, for a monopolist, the marginal revenue curve lies beneath the demand curve, because they face a downward-sloping demand curve and must lower the price to sell additional units, which affects the revenue gained from previously sold units. Hence, the formula would take into account the market demand curve, and the slope of this curve would factor into determining the marginal revenue for each additional unit sold.
In order to calculate the deficit figure of the marginal revenue of the private seller, we need to understand the demand equation and how it relates to revenue. The demand equation represents the relationship between the price of a product and the quantity that consumers are willing to buy at that price. It can be written as: Q = a - bP, where Q is the quantity, P is the price, and a and b are constants. The total revenue can be calculated by multiplying the price and the quantity sold, which is Q*P. The marginal revenue is then calculated by finding the change in total revenue divided by the change in quantity. So, the formula for the deficit figure of the marginal revenue of the private seller based on the given demand equation is: MR = (Q2*P2) - (Q1*P1), where MR is the marginal revenue, Q2 and Q1 are the quantities sold at two different price points, and P2 and P1 are the corresponding prices.