When would a good’s total utility and marginal utility be the same?

Answer :

Utility is the satisfaction a person derives from the consumption of a good or service. Total utility is the total satisfaction received from consuming a given total quantity of a good or service, while marginal utility is the satisfaction gained from consuming an additional quantity of that item. Sometimes, economists like to subdivide utility into individual units that they call utils. However, because utility is subjective, meaning that it differs from person to person, and because it varies continuously, depending on the quantity consumed, an util cannot actually be measured, but is simply a heuristic device that allows economists to talk about the degree of satisfaction for a product or service.Marginal utility always declines for each successive quantity of consumption. If you like ice cream, and you eat one scoop, the first scoop will provide the greatest satisfaction. If you eat another scoop, you'll probably enjoy that also, but the satisfaction will be less than for the first. At some point, you will not want any more ice cream. The marginal utility will drop to zero and may even become negative. This illustrates the law of diminishing marginal utility. Marginal utility declines for everything, including money. Although many people want to amass great wealth, each dollar accumulated becomes worth less and less, because the marginal utility of what it can buy declines.

Declining marginal utility explains why the demand curve slopes downward as the supply quantity is increased, and why people will only consume more if the price declines, since people's willingness to pay also declines.

Marginal utility is also related to the elasticity of demand. If demand is inelastic, then the quantity demanded drops off slowly as the price increases, indicating that the marginal utility of the product or service is high; with elastic demand, demand quantity drops off sharply, indicating a low marginal utility for the product, so the consumer is not willing to pay a higher price.