In microeconomics, utility represents a way to relate the amount of goods consumed to the amount of happiness or satisfaction a consumer gets. Marginal utility tells how much marginal value or satisfaction a consumer gets from consuming an additional unit of good. Microeconomic theory states that consumer choice is made on margins, meaning consumers constantly compare marginal utility from consuming additional goods to the cost they have to incur to acquire such goods. A consumer buys goods as long as the marginal utility for each additional unit exceeds its price. A consumer stops consuming additional goods as soon as the price exceeds the marginal utility.

Law of Diminishing Marginal Utility

In microeconomics, marginal utility and the law of diminishing marginal utility are the fundamental blocks that provide insight into the consumer choice of quantity and type of goods to be consumed. The law of diminishing marginal utility states the marginal utility from an additional unit of consumption declines as the quantity of consumed goods increases. Consumers choose their baskets of goods by equating marginal utility of a good to its price, which is a marginal cost of consumption.

Law of Demand

The price a consumer is willing to pay for a good depends on his marginal utility, which declines with each additional unit of consumption, according to the law of diminishing marginal utility. Therefore, the price decreases for a normal good when consumption increases. The price and quantity demanded are inversely related, which represents the fundamental law of demand in consumer choice theory.