A person spends 30% of his income on food, 20% on transportation, and 50% of the remaining amount on house rent. What percentage of his income is left?

Question: A person spends 30% of his income on food, 20% on transportation, and 50% of the remaining amount on house rent. What percentage of his income is left?

Solution:
Let, total income = 100
Total expense food and transportation = 30 + 20 = 50
∴ Remaining = (100 - 50) = 50

∴ Expense on house rent = 50 × (50/100) = 25
∴ Remaining after all expense = 50 - 25 = 25

The person is left with 25% of his income.