Radha saves 25% of her income. If her expenditure increases by 20% and her income increases by 29%, then her savings increase by :

56%

Let the income of Radha is 100x

Saving = \(\frac{1}{4}\) × 100X = 25x

Expenditure = 100x - 25x = 75x

The new increased income = 100X + 100X ×  \(\frac{29}{100}\) = 100X + 29X = 129X

The new expenditure = 75X + 75X × \(\frac{20}{100}\) = 75X + 15X = 90X

The new saving = 129X – 90X = 39X

Increases percent of saving =   \(\frac{14x}{25x}\) × 100 = 56%