By Pathantu · Published 6 October 2026 · Original practice, not PYQ
Method
Percentage = part ÷ base × 100. “A is what percent of B?” uses B as the denominator.
For an increase of r%, multiply by (1+r/100); for a decrease, multiply by (1−r/100). To reverse a change, divide by that multiplier.
Successive changes use different bases. Multiply their factors instead of adding percentages.
Six questions: try first, then open the solution
1. 45 out of 60 students passed. What percentage passed?
Show worked solution
45/60 × 100 = 75%. The base is all 60 students.
2. A price rises from ₹400 to ₹500. Find the percentage increase.
Show worked solution
Increase=₹100. Divide by the original ₹400: 100/400 × 100 = 25%.
3. A bag costs ₹720 after a 20% discount. Find its marked price.
Show worked solution
720 is 80% of the marked price: 720/0.80 = ₹900. Check: 900−180=720.
4. A quantity rises by 20%, then falls by 20%. Find the net change.
Show worked solution
Start with 100: 100×1.20×0.80=96. Net decrease=4%, not zero.
5. A pass rate rises from 40% to 50%. Describe the rise in two ways.
Show worked solution
10 percentage points; relative increase=(50−40)/40×100=25%.
6. A is 25% greater than B. By what percent is B smaller than A?
Show worked solution
Take B=100, A=125. Difference=25; 25/125×100=20%. The second base is A.
Check your reasoning
Label the base, change and final value separately. A percentage without its base is incomplete information.
For each wrong answer, write the incorrect step and solve the question again without the solution. These open lessons need no login; timed quizzes require a student account.
Practise the free SSC subject quiz: 20 questions, 20 minutes, +2 / −0.50Continue learning
- Time and work: rates, remaining work and leaks
- Syllogisms: test a conclusion with counterexamples
- Data interpretation: totals, ratios and weighted averages