A person could save 20% of his income. A year later, his income increased by 25% but he could save the same amount only as before. By what percentage has his expenditure increased?

31.25%

Let salary of Men = 100x

Saving = 20% of 100x = 20x

Expenditure = 100x - 20x = 80x

New income = 100x + 25% of 100x = 125x

Saving remains same . So, saving = 20x

New expenditure = 125x - 20x = 105x

Increase in Expenditure = \(\frac{105x - 80x }{80x }\) × 100

= 31.25%