28 Marginal Costs

This lesson explains the key cost concepts in economics, starting with private costs — the costs directly paid by producers or consumers — and external costs, which are costs imposed on third parties not involved in the transaction, such as pollution or congestion. When we combine these, we get social cost, which represents the true total cost to society. We then introduce marginal concepts: marginal private cost (the extra cost to the producer of one more unit), marginal external cost (the extra cost imposed on others), and marginal social cost, which equals the sum of the two. In cases of negative externalities like pollution, marginal social cost lies above marginal private cost, while with positive externalities like education, it lies below. Understanding these relationships is essential for analyzing market failure and government intervention. For expert economics tutoring and exam support, visit AxiomTutoring.com.