Nikhil's monthly income is 25% more than Owais's. Nikhil saves 20% of his income and Owais saves 25% of his. The ratio of Nikhil's monthly expenditure to Owais's monthly expenditure is:

Let Owais earn ₹100, so Nikhil earns ₹125. Owais saves ₹25 and spends ₹75; Nikhil saves 20% of 125 = ₹25 and spends ₹100. Expenditures are 100 : 75 = 4 : 3. The incomes are in 5 : 4 and the savings happen to be equal (1 : 1), but neither is the expenditure ratio — the two men save different FRACTIONS of different incomes.