About Lesson
- This economic principle explains one of the basic production relationships viz., factor-factor relationship.
- It guides in the determination of least cost combination of resources.
- It helps in making a management decision of how to produce.
- The principle of factor substitution says that go on adding a resource so long as the cost of resource being added is less than the saving in cost from the resource being replaced.
Profit or Decision rules
- If Marginal rate of substitution (MRS) is greater than price ratio (PR) costs can be reduced by using more of added resource.
ΔX 2/ ΔX1 > P X1/ P X2 increase the use of X1
- If Marginal rate of substitution (MRS ) is less than price ratio (PR), costs can be reduced by using more replaced resource.
Δ X 2/ Δ X1 < P X1/ P X2
- Least costs combination of resources is at the point where MRS=PR
ΔX1/ Δ X2 = PX2/ P X1
Or, ΔX2/ Δ X1 = PX1/ P X2