If the market price is $40 in a perfectly competitive market, what is the marginal revenue from selling the fifth unit?

1. Break Down the Problem

To find the marginal revenue from selling the fifth unit in a perfectly competitive market, we need to understand that in such a market, the price is constant and equal to the marginal revenue.

2. Relevant Concepts

• In a perfectly competitive market, the price (P) is equal to the marginal revenue (MR).
• Therefore, if the market price is $40, the marginal revenue from selling each additional unit is also$40.

3. Analysis and Detail

Since the market price remains constant at $40 for all units sold, the marginal revenue for any additional unit sold, including the fifth unit, will not change. Each unit sold generates the same amount of revenue, which is equal to the market price.

4. Verify and Summarize

Given that the price is consistent across all units in a perfectly competitive market, we can confirm that the marginal revenue remains at $40.

Final Answer

The marginal revenue from selling the fifth unit is $40.