Percentage Tricks for SSC CGL (Quick Answer)
The two percentage tricks that solve most SSC CGL questions are the fraction table (12.5% = 1/8, 16.66% = 1/6, 14.28% = 1/7 and so on) and the successive change formula: net change = a + b + ab/100. For example, a 20% rise followed by a 20% fall gives 20 − 20 + (20 × −20)/100 = −4%, a net fall of 4%, not zero.
Key takeaway: Turn every percentage into a fraction, every change into a multiplier (+25% = ×5/4, −20% = ×4/5), and chain the multipliers. "If A is x% more than B, B is x/(100 + x) × 100% less than A" handles the consumption and comparison questions.
Percentage is the base of profit and loss, SI and CI, DI and averages, and SSC CGL Tier 1 usually has one or two direct questions plus several that depend on it. Every worked answer below was recomputed in Python.
Percentage Formulas for SSC CGL
| Use | Formula |
|---|---|
| x% of N | (x/100) × N |
| What percent is A of B | (A/B) × 100 |
| Percentage change | (New − Old)/Old × 100 |
| Value after x% increase | Old × (100 + x)/100 |
| Value after x% decrease | Old × (100 − x)/100 |
| Successive changes a% and b% | a + b + ab/100 (use negative signs for falls) |
| A is x% more than B; B is less than A by | x/(100 + x) × 100 % |
| A is x% less than B; B is more than A by | x/(100 − x) × 100 % |
| Price up x%; cut in consumption to keep spending same | x/(100 + x) × 100 % |
| Price down x%; increase in consumption | x/(100 − x) × 100 % |
| Population after n years at r% | P × (1 + r/100)ⁿ |
| Depreciation after n years at r% | P × (1 − r/100)ⁿ |
Fraction to Percentage Table (Must Memorise)
| Fraction | Percent | Fraction | Percent |
|---|---|---|---|
| 1/2 | 50% | 1/9 | 11.11% |
| 1/3 | 33.33% | 1/10 | 10% |
| 1/4 | 25% | 1/11 | 9.09% |
| 1/5 | 20% | 1/12 | 8.33% |
| 1/6 | 16.66% | 1/16 | 6.25% |
| 1/7 | 14.28% | 1/20 | 5% |
| 1/8 | 12.5% | 3/8 | 37.5% |
| 5/6 | 83.33% | 7/8 | 87.5% |
Multiplier habit: +12.5% = ×9/8, +16.66% = ×7/6, −14.28% = ×6/7, +33.33% = ×4/3, −25% = ×3/4.
Successive Percentage Change Shortcut (a + b + ab/100)
| Changes | Net effect |
|---|---|
| +10%, +20% | 10 + 20 + 2 = +32% |
| +20%, −20% | 20 − 20 − 4 = −4% |
| −20%, +20% | Same: −4% (order does not matter) |
| Discounts 20% and 10% | −20 − 10 + 2 = −28% (a single discount of 28%) |
| Length +20%, breadth −10% (area) | 20 − 10 − 2 = +8% |
| +10% three times | 1.1³ = 1.331, so +33.1% |
For more than two changes, multiply the factors instead of applying the formula twice.
Percentage Questions for SSC CGL with Solutions
Q1. A's income is 25% more than B's. By what percent is B's income less than A's? 25/125 × 100 = 20%.
Q2. The price of sugar rises by 25%. By what percent must a family cut consumption to keep spending the same? 25/125 × 100 = 20%.
Q3. The price of rice falls by 20%. By what percent can a family increase consumption for the same spending? 20/80 × 100 = 25%.
Q4. The population of a town is 10,000 and grows by 10% a year. Find it after 2 years. 10,000 × 1.1 × 1.1 = 12,100.
Q5. A man earns ₹40,000 and spends ₹30,000. His income rises by 20% and spending by 10%. By what percent do his savings rise? New income ₹48,000, new spending ₹33,000, savings ₹15,000 (up from ₹10,000): 50%.
Q6. x is 20% of y and y is 25% of z. What percent of z is x? 0.20 × 0.25 = 0.05, so 5%.
Q7. A student scoring 30% fails by 15 marks; another scoring 40% gets 35 marks more than the pass mark. Find the maximum marks and the pass percentage. The 10% gap equals 15 + 35 = 50 marks, so maximum = 500. Pass mark = 150 + 15 = 165, which is 33%.
Q8. In an election between two candidates, the winner gets 58% of the valid votes and wins by 1,440 votes. Find the total valid votes. Margin = 58% − 42% = 16%. 16% = 1,440, so total = 9,000.
Q9. A number increased by 12.5% becomes 450. Find the number. 12.5% = 1/8, so the number × 9/8 = 450, number = 400.
Q10. Two successive discounts of 20% and 10% equal what single discount? −20 − 10 + (200/100) = −28%, a single discount of 28%.
Q11. Fresh fruit has 90% water and dry fruit has 20% water. How much dry fruit comes from 100 kg of fresh fruit? Pulp stays the same: 10% of 100 = 10 kg = 80% of dry fruit. Dry fruit = 12.5 kg.
Q12. A machine worth ₹8,000 depreciates by 10% a year. Find its value after 2 years. 8,000 × 0.9² = ₹6,480.
Percentage in Profit, Loss and Discount (Linked Questions)
Q13. An article costs ₹400. It is marked 25% above cost and sold at a 10% discount. Find the profit percent. Marked price = 400 × 5/4 = 500. Selling price = 500 × 9/10 = 450. Profit = 50/400 = 12.5%.
Q14. The cost price of 20 articles equals the selling price of 16 articles. Find the profit percent. Profit = (20 − 16)/16 × 100 = 25%.
These two show why percentage comes first: profit, discount and interest are all percentage changes on a base.
Percentage Quick Revision Table
| Question says | Do this |
|---|---|
| "x% more than" | Multiply by (100 + x)/100 |
| "x% less than" | Multiply by (100 − x)/100 |
| "What percent less/more is the other" | Divide the difference by the other base |
| Two changes one after another | a + b + ab/100 |
| Three or more changes | Multiply the factors |
| Pass marks or election margin | Percentage gap = marks or vote gap |
| Fresh to dry | Keep the non-water part fixed |
Percentage in Data Interpretation and Current Affairs
Q15. Sales rose from 240 units to 300 units. Find the percentage increase. (300 − 240)/240 × 100 = 25%.
Q16. A rate rises from 5.25% to 5.50%. Is that a rise of 0.25% or 4.76%? Both phrases appear, so know the difference. The rate rose by 0.25 percentage point. As a relative change it is 0.25/5.25 × 100 ≈ 4.76%. This is exactly how a repo rate change is reported, for example in our repo rate history year wise note.
Percentage point vs percent: a percentage point is the plain difference between two percentages; a percent change compares that difference with the starting value. Bank and SSC questions on budgets, inflation and interest rates often test this.
Percentage Short Tricks That Save Time
- Swap trick: x% of y = y% of x. 16% of 25 = 25% of 16 = 4.
- Split trick: 15% of 80 = 10% (8) + 5% (4) = 12.
- Use multipliers, not two steps: a 25% rise then a 20% fall is 5/4 × 4/5 = 1, so no change.
- Gap method for exams and elections: the percentage gap between two people equals the marks or vote gap (Q7, Q8).
- Fixed part method: in dry-fruit or mixture questions, the part that does not change carries the answer (Q11).
- Reverse percentage: the original = new ÷ multiplier (Q9).
Percentage feeds straight into SI and CI difference formulas and statistics formulas for SSC CGL, so learn these before moving on.
Common Mistakes in Percentage Questions
| Mistake | Correct |
|---|---|
| +20% then −20% = 0 | Net −4% |
| "A is 25% more than B" so "B is 25% less than A" | B is 20% less |
| Adding successive discounts (20% + 10% = 30%) | Single discount is 28% |
| Taking a percentage of the new value when the base is the old value | Always check the base |
| Using population growth simple-interest style | Growth compounds: P(1 + r/100)ⁿ |
Percentage Practice Questions for SSC CGL (with Answers)
- 40% of 120 + 25% of 80 = ? Answer: 68.
- The price of a product rises by 50%. By what percent should consumption fall to keep spending the same? Answer: 33.33%.
- A number is decreased by 20% and then increased by 20%. Net change? Answer: −4%.
- A is 20% less than B. By what percent is B more than A? Answer: 25%.
- 60% of a number is 48. The number? Answer: 80.
- Length of a rectangle +20%, breadth −10%. Change in area? Answer: +8%.
- A candidate scoring 35% fails by 20 marks; another scoring 45% gets 30 marks more than the pass mark. Maximum marks? Answer: 500 (pass mark 195).
- +10%, +10%, +10% in three years. Total increase? Answer: 33.1%.
- 16% of 25 = ? Answer: 4.
- Successive changes of +10% and +20%. Net change? Answer: +32%.
Practise these in the SSC CGL Percentage Mock Test 01, SSC CGL Percentage Mock Test 02 and SSC CHSL Percentage Mock Test 01.
Percentage FAQs
What is the formula for successive percentage change?
Net change = a + b + ab/100, where a and b are the two changes (negative for a fall).
If A is 25% more than B, how much less is B than A?
25/125 × 100 = 20%.
What are the most important percentage tricks for SSC CGL?
The fraction table, multipliers, successive change, the consumption formula and the gap method for marks and votes.
How many percentage questions come in SSC CGL?
One or two direct questions in Tier 1, but percentage is used inside profit and loss, interest, DI and averages, so it affects many more.
Is percentage important for bank exams too?
Yes. IBPS and SBI papers use it in arithmetic word problems and data interpretation, so the same tricks apply.
Practice Next
- Topic tests where these percentage shortcuts apply: SSC GD Percentage Mock Test 02 and SSC GD Profit and Loss Mock Test 02.
- New SSC CGL practice: SSC CGL Percentage Mock Test 04 and SSC CGL Maths Mini Mock Test 05.
- Mock tests: SSC CGL Percentage Mock Test 03 and SSC CHSL Percentage Mock Test 02.
- New sectional tests: SSC MTS Numerical and Mathematical Ability Sectional Mock Test 01: Session 1 Pattern 2026 (20 Questions) and RRB NTPC Mathematics Sectional Mock Test 01: CBT 1 Pattern 2026 (30 Questions).
- New SSC topic test: SSC MTS Percentage, Profit and Loss Mock Test 01: Discounts and Marked Price (15 Questions).
- New SSC topic test: SSC CHSL Profit and Loss Mock Test 01.
- Related notes: time and work tricks for SSC CGL, algebra formulas for SSC CGL, mensuration formulas for SSC CGL, mixture and alligation questions, partnership questions for bank exams and RRB NTPC maths formulas; also see profit and loss tricks for SSC CGL and ratio and proportion for SSC CGL, plus average tricks for SSC CGL, bar graph data interpretation, plus discount tricks for SSC CGL.
- Exam details: SSC CGL 2026 notification.
- Browse all study notes.