The three percentage questions
- What is 15% of 2,000? → 2000 × 15 ÷ 100 = 300. Used for discounts, tips, commissions, GST.
- 450 is what % of 600? → 450 ÷ 600 × 100 = 75%. Used for marks, attendance, targets.
- % change from 80 to 100? → (100−80) ÷ 80 × 100 = +25%. Used for salary hikes, price changes, growth.
Quick exam-marks tip
To convert marks to percentage: (marks obtained ÷ total marks) × 100. For CGPA-to-percentage, most Indian boards use CGPA × 9.5 — but check your board's official formula, as universities differ.
FAQs
What's the difference between percentage and percentile?
Percentage measures your score against the maximum. Percentile measures your rank against other candidates — a 95th percentile means you scored better than 95% of test-takers, regardless of your actual marks.
Why is percentage decrease not the reverse of increase?
A 20% increase followed by a 20% decrease doesn't return to the start: 100 → 120 → 96. Percentage change is always measured from the starting value.