Shortcut Trick
Initial Savings = 30,000 − 20,000 = ₹10,000
New Income = 30,000 + 10,000 = ₹40,000
New Savings = 40,000 − 25,000 = ₹15,000
Percentage Increase = [(15,000 − 10,000) ÷ 10,000] × 100 = 50%
∴ The correct answer is 50%.
Alternate Method
Given:
Initial Income (I1) = ₹30,000, Initial Expenditure (E1) = ₹20,000
New Income (I2) = 30,000 + 10,000 = ₹40,000, New Expenditure (E2) = ₹25,000
Formula Used:
Savings = Income − Expenditure
Percentage Increase = (Increase ÷ Original Value) × 100
Calculations:
⇒ Initial Savings (S1) = 30,000 − 20,000 = ₹10,000
⇒ New Savings (S2) = 40,000 − 25,000 = ₹15,000
⇒ Increase in Savings = 15,000 − 10,000 = ₹5,000
⇒ Percentage Increase = (5,000 ÷ 10,000) × 100
⇒ Percentage Increase = 0.5 × 100 = 50%
∴ The correct answer is 50%.
Additional Information
Income-Expenditure Relation
Income is always the sum of Expenditure and Savings (I = E + S). Any change in one affects at least one other component.
Percentage Change
Percentage change = [(Final Value − Initial Value) ÷ Initial Value] × 100. Always ensure the denominator is the original/base value.
Base Shift
If expenditure increases at a higher rate than income, the savings percentage increase might be lower or even negative depending on the initial values.