Why this is mistaken
Equilibrium is a consistency condition inside stated demand and supply relationships. It does not authenticate those relationships, show the path of adjustment, or transform a model output into an observed transaction.
Use a three-part repair. First reconcile quantity demanded and quantity supplied at the solved price. Second label the result a model equilibrium and name evidence needed to observe or estimate the market. Third list the additional assumptions and value criteria required for a welfare or fairness claim.
Someone who computes the crossing correctly but writes “therefore fair” has not completed the objective.
Where to watch
When this mistake may appear
- Demand and supply equations cross cleanly.
- A prompt calls the crossing the market-clearing price.
Check your work
Your work may contain this mistake if:
- Calls the solved price an observed sale without transaction evidence.
- Says equilibrium is fair by definition.
- Claims welfare efficiency while omitting market power, external effects, information, rights, or distribution.