**Consumer's Equilibrium in Case of One Commodity**

Consumer's equilibrium refers to the state in which a consumer maximizes their satisfaction or utility by allocating their limited income to purchase a certain quantity of goods and services. In the case of one commodity, the consumer's equilibrium is determined by the interaction of the consumer's preferences, budget constraint, and the market price of the commodity.

**1. Consumer's Preferences**
The consumer's preferences or tastes play a crucial role in determining their equilibrium. Preferences are typically represented by an individual's utility function, which indicates the satisfaction or pleasure derived from consuming different quantities of a commodity. The utility function is subjective and varies from person to person. It is assumed that individuals prefer more of a commodity to less, and the satisfaction derived from each additional unit decreases gradually (law of diminishing marginal utility).

**2. Budget Constraint**
The consumer's budget constraint reflects the limited income or resources available to them. In the case of one commodity, the budget constraint is straightforward – it is the total income of the consumer. The consumer's income determines the maximum quantity of the commodity they can afford to purchase at a given price.

**3. Market Price**
The market price of the commodity is determined by the interaction of demand and supply in the market. It represents the rate at which the commodity can be exchanged for money. The consumer takes this price as given and makes decisions based on it.

**Consumer's Equilibrium Condition**
The consumer's equilibrium condition is achieved when the consumer allocates their limited income in such a way that the marginal utility derived from the last unit of money spent on the commodity is equal to the marginal utility derived from the last unit of the commodity itself. Mathematically, this can be represented as:

MUc/Pc = MUm

Where:
- MUc denotes the marginal utility of the commodity
- Pc represents the price of the commodity
- MUm represents the marginal utility of money

This condition ensures that the consumer is maximizing their satisfaction or utility given their preferences, budget constraint, and the market price of the commodity. If the marginal utility of the commodity divided by its price is greater than the marginal utility of money, the consumer should consume more of the commodity. On the other hand, if the marginal utility of the commodity divided by its price is less than the marginal utility of money, the consumer should consume less of the commodity.

By reaching this equilibrium condition, the consumer is effectively allocating their limited income in a way that maximizes their satisfaction and utility from consuming the one commodity.