Study Material — 15 PYQs (2020–2020) · Concept Notes · Shortcuts
IBPS Clerk Percentage Change is a frequently tested subtopic — 15 previous year questions from 2020–2020 papers are included below with concept notes, key rules and shortcut tricks.
IBPS Clerk Percentage Change — Past Exam Questions
15 questions from actual IBPS Clerk papers · all shown free · click option to reveal solution
Exam Q 12020Previous Year Pattern
A shopkeeper reduced the price of an item by 25%. The reduced price is ₹450. What was the original price?
Exam Q 22020Previous Year Pattern
A student's marks increased from 60 to 75. What is the percentage increase in marks?
Exam Q 32020Previous Year Pattern
A product's price increased by 10%, then by another 20%. What is the total percentage increase?
Exam Q 42020Previous Year Pattern
If a quantity increases by 50% and then decreases by 50%, what is the net percentage change?
Exam Q 52020Previous Year Pattern
The population of a town decreased from 80,000 to 72,000. What is the percentage decrease?
Exam Q 62020Previous Year Pattern
The price of a shirt was increased by 20%. If the new price is ₹600, what was the original price?
Exam Q 72020Previous Year Pattern
The value of a car depreciates by 15% in the first year and by 10% in the second year. If the initial value was ₹4,00,000, what is the value of the car after two years?
Exam Q 82020Previous Year Pattern
The price of a commodity increases by 25% in the first year and then decreases by 20% in the second year. What is the net percentage change in the price over the two years?
Exam Q 92020Previous Year Pattern
A shopkeeper marks up the cost price of an item by 40%. He then offers a discount of 30% on the marked price. If the cost price is ₹500, what is the selling price and the overall profit/loss percentage?
Exam Q 102020Previous Year Pattern
A retailer buys goods at a 20% discount from the wholesale price. He then sells them at 25% above the wholesale price. What is his profit percentage based on his cost price?
Exam Q 112020Previous Year Pattern
A company's revenue increased by 30% in Q1 and decreased by 20% in Q2. In Q3, it increased by 25%. If the revenue at the end of Q3 is ₹1,95,000, what was the initial revenue?
Exam Q 122020Previous Year Pattern
A car's value depreciates by 15% in the first year and by 10% in the second year. If the car is worth ₹3,06,000 after two years, what was its original value? (Assume depreciation is calculated on the value at the beginning of each year.)
Exam Q 132020Previous Year Pattern
A student's marks increased from 320 to 400. Later, due to re-evaluation, the marks decreased by 10% from 400. What is the net percentage change from the original 320 marks?
Exam Q 142020Previous Year Pattern
A shopkeeper marks up goods by 60% above cost price. He then offers a discount of 25% on the marked price. What is his profit percentage?
Exam Q 152020Previous Year Pattern
A product's price increased by 25% in the first year. In the second year, the new price decreased by 20%. If the final price is ₹3,000, what was the original price?
Concept Notes
Percentage Change— Rules & Concept
Core ConceptRead this first — the foundation of the topic
Percentage change is the difference between the original value and the new value, expressed as a percentage of the original value. This concept appears in almost every SSC CGL paper and forms the backbone of profit-loss, simple interest, and data interpretation questions. Core Concept: When any quantity increases or decreases, we calculate the percentage change to measure the rate of change. For example, if your salary increases from Rs 20,000 to Rs 25,000, the percentage increase is 25%.
Formula BlockMemorise — at least one formula appears in every paper
Block:
• Percentage Increase = [(New Value - Original Value) / Original Value] × 100
• Percentage Decrease = [(Original Value - New Value) / Original Value] × 100
• New Value after x% increase = Original Value × (100 + x)/100
• New Value after x% decrease = Original Value × (100 - x)/100
• Successive percentage changes: If a value changes by a% then b%, final change = [a + b + (ab/100)]%
Exam PatternsWhat examiners ask — read before attempting PYQs
SSC loves asking percentage change in population growth, salary hikes, price fluctuations, and successive discounts. Questions often involve finding original values when final values and percentage changes are given.
ShortcutsUse these to save 30–60 seconds per question
1
Two successive increases of x% = (x + x + x²/100)% total increase
2
One increase of x% followed by decrease of x% = (x²/100)% net decrease
3
25% increase means multiply by 1.25
4
20% decrease means multiply by 0.8
5
12.5% increase means multiply by 9/8
Worked ExampleSolve this step-by-step before moving on
1
Step 1
Identify original value = 50,000, new value = 65,000
2
Step 2
Find increase = 65,000 - 50,000 = 15,000
3
Step 3
Apply formula = (15,000/50,000) × 100 = 30%
Answer: 30% increase
Worked Example 2:
A number is first increased by 20% and then decreased by 15%. Find the overall percentage change.
1
Step 1
Let original number = 100 (always take 100 for easier calculation)
2
Step 2
After 20% increase = 100 × 1.2 = 120
3
Step 3
After 15% decrease = 120 × 0.85 = 102
4
Step 4
Overall change = 102 - 100 = 2
5
Step 5
Percentage change = 2% increase
Alternative: Using formula = 20 + (-15) + (20×(-15)/100) = 20 - 15 - 3 = 2% increase
Shortcut Trick #3: Percentage to fraction conversions:
• 12.5% = 1/8, 16.67% = 1/6, 33.33% = 1/3, 66.67% = 2/3
• These help in quick mental calculations during exams.
Exam TrapsCommon mistakes students make — avoid these
#1: Students often confuse which value to use as base. Remember: percentage change is always calculated on the ORIGINAL value, not the new value. If price changes from Rs 100 to Rs 120, the base is Rs 100, not Rs 120.
Many students calculate (20/120) × 100 instead of (20/100) × 100, leading to wrong answers.
Exam Strategy: Practice reverse calculations where you find original values from final values and percentage changes. SSC frequently tests this concept in tricky word problems involving multiple successive changes.
Key Points to Remember
Percentage change = [(New Value - Original Value) / Original Value] × 100
Always use original value as denominator, never the new value
Successive changes formula: a + b + (ab/100) for changes of a% and b%