Consumer Choice and Utility Maximization

Jul 9, 2025

Overview

This lecture introduces the concept of making consumer choices using marginal utility per dollar, focusing on step-by-step decisions to maximize satisfaction within a budget.

Marginal Utility and Consumer Choice

  • Marginal utility is the extra satisfaction from consuming one more unit of a good.
  • Consumer choices should consider both satisfaction (utility) and the price of goods.
  • Instead of comparing whole bundles, decisions are made one item and one dollar at a time.

Marginal Utility per Dollar ("Bang for Your Buck")

  • Marginal utility per dollar is calculated by dividing marginal utility by the good's price.
  • This method helps determine which purchase brings the most satisfaction for each dollar spent.
  • For each purchase, compare the marginal utility per dollar between goods to decide which to buy next.

Step-by-Step Optimal Decision Process

  • Start with a budget (example: Jose has $56).
  • For each dollar spent, buy the item with the highest marginal utility per dollar.
  • Continue purchases, updating remaining budget after each item until all money is spent.
  • If two choices have equal marginal utility per dollar, the consumer is indifferent between them.

Consumer Equilibrium

  • Consumer equilibrium occurs when the marginal utility per dollar is equal across all goods.
  • If marginal utility per dollar is not equalized, the choice is not optimal.
  • This principle guides consumers to allocate their budget most efficiently between goods.

Key Terms & Definitions

  • Marginal Utility — Additional satisfaction gained from consuming one more unit of a good.
  • Marginal Utility per Dollar — Marginal utility divided by the price of the good; measures satisfaction per $1 spent.
  • Consumer Equilibrium — The state where marginal utility per dollar is equal for all goods purchased, indicating optimal allocation.

Action Items / Next Steps

  • Review the next video example for a detailed calculation walkthrough.
  • Prepare for the final lecture video covering this chapter.