Worked-example setupScope and assumptions
- The Linden baseline demand and supply functions are supplied fictional teaching models on common price, quantity, product, quality, market, and period units.
- The functions are linear over a domain containing one positive crossing and omit market power, taxes, external effects, search, contracts, inventory, and adjustment lags.
- No observed transaction, fairness criterion, accounting measurement, or pricing authority is supplied.
- Period
- One representative fictional week
- Units
- USD per qualifying chair and qualifying chairs per week
- Rounding
- Exact whole-dollar price and whole-chair model quantity
Solve the equality
The supplied baseline functions are:
Qd = 1,400 - 10P
Qs = 200 + 10P
At equilibrium, set them equal:
1,400 - 10P = 200 + 10P
1,200 = 20P
P* = $60 per chair
Substitute into both sides
Demand gives 1,400 - 10 × 60 = 800 chairs per week. Supply gives
200 + 10 × 60 = 800. The zero difference is the essential reconciliation;
solving a price without checking both quantities leaves a sign or transcription
error undetected.
Stop at the model boundary
The result is a clearing point under supplied equations. It is not evidence that $60 was quoted, accepted, delivered, paid, or recognized. It does not prove instantaneous adjustment or that every buyer and seller traded. It says nothing by itself about fairness, ability to pay, external costs, market power, legal constraints, or distribution.
A precise conclusion is: “The stipulated Linden baseline model has a unique positive equilibrium of $60 per chair and 800 chairs per week; both equations reconcile at that point.” Stronger claims require stronger evidence.
Verified calculation · economics foundations analysis
The curriculum loader recomputed this example before it entered the site build. Expand any structured input to inspect the stated facts.
- linear markets
- 1 field
Inspect data
{
"linden_equilibrium": {
"demand_intercept_quantity": 1400,
"demand_quantity_per_price": 10,
"price_checks": {
"solved_price": 60
},
"supply_intercept_quantity": 200,
"supply_quantity_per_price": 10
}
}Recomputed result
| Measure | Value |
|---|---|
| equilibrium price | 60 |
| equilibrium quantity | 800 |
| equilibrium quantity demanded | 800 |
| equilibrium quantity difference | 0 |
| equilibrium quantity supplied | 800 |
| solved price at equilibrium | 1 |