Question -
Answer -
The ratio of change in consumption (C) to change in income (Y) is known as marginal propensity to consume. It indicates the proportion of additional income that is being spent on consumption.
The sum of MPC and MPS is equal to one. It can be proved as under: We know: ΔY = ΔC + ΔS
Dividing both sides by AY, we get,ΔY/ΔY=ΔC/ΔY + ΔS/ΔY or 1=MPC+MPS
[ΔY/ΔY=1; ΔC/ΔY =MPC ΔS/ΔY=MPS]
MPC + MPS = 1 because total increment in income is either used for consumption or for saving.