The long run equilibrium in monopolistic competition is characterized by which of the following conditions ?

Question

Accepted Answer

The correct option is 1:

The long-run equilibrium in monopolistic competition is characterized by two essential conditions that stem from the market structure. First, for any profit-maximizing firm, equilibrium always requires that Marginal Revenue (MR) equals Long-Run Marginal Cost (LMC). This is the standard profit-maximizing rule that applies to all market structures, including monopolistic competition, where MR and LMC intersect to determine the equilibrium output. Second, the long run specifically dictates that economic profit must be zero. This zero-profit condition is enforced by the free entry and exit of firms, a characteristic shared with perfect competition. If firms were making supernormal profits (Price > Long-Run Average Cost or P > LAC), new firms would enter, shifting the demand curve for existing firms down until P = LAC. If firms were incurring losses (P < LAC), firms would exit, shifting the demand curves up until P = LAC. Therefore, the long-run equilibrium conditions are the profit-maximizing output rule (MR = LMC) and the zero-economic profit rule (P = LAC).

The incorrect option is 2: MR > LMC and P = LAC

While P = LAC correctly represents the zero-economic profit condition in the long run, MR > LMC indicates that the firm has not reached its profit-maximizing output. If MR is greater than LMC, the firm could increase its total profit by increasing its output, meaning it is not in equilibrium.

The incorrect option is 3: MR = LMC and P > LAC

MR = LMC satisfies the profit-maximizing output condition. However, P > LAC means the firm is earning supernormal or abnormal profits. In a monopolistically competitive market, these supernormal profits would attract new firms, causing the existing firm's demand curve to shift left, eliminating the economic profit until P = LAC is achieved. Therefore, this condition describes a short-run or temporary equilibrium, not the long-run equilibrium.

The incorrect option is 4: MR > LMC and P > LAC

Both conditions are characteristic of a firm that is neither maximizing profits nor is in a long-run stable state. MR > LMC means the firm is not producing at the profit-maximizing level, and P > LAC means the firm is earning supernormal profits, which would invite new entrants and disrupt the equilibrium in the long run.