If Maria estefan disposable IncomeIncreaseFrom 600 to 650
And her level of personal consumption expenditures increase from 450 to 520 You may conclude that’s her marginal propensity to
i=650−600600520−450450=0.54.i=\frac{\frac{650-600}{600}}{\frac{520-450}{450}}=0.54.i=450520−450600650−600=0.54.