IOCL 2026 aptitude
Quantitative, reasoning, and verbal drills with solutions
This page collects IOCL placement papers from 2026 with practice questions, worked solutions, and the exam pattern students reported that cycle. Use it when you want drive history: what the first round looked like, which topics repeated, and how to approach solutions. Work the sets below under a timer, then compare with newer material so your prep matches both established IOCL patterns and recent shifts.
IOCL 2026 aptitude
Quantitative, reasoning, and verbal drills with solutions
IOCL 2026 coding
DSA practice aligned to IOCL online assessments
IOCL interview experience
Round structure and tips from student reports
IOCL prep guide
Study plan and weekly schedule
Timed placement-style MCQs with score and explanations after you submit. Use it to check speed and accuracy before the real test.
Quantitative
Reading Comprehension (2024 - Real Question)
According to the passage, a major consequence was a significant increase in urban populations due to migration for work opportunities.
Verbal
Problem: Choose the correct sentence: a) Neither the students nor the teacher were present b) Neither the students nor the teacher was present c) Neither the students or the teacher was present
With "neither...nor", the verb agrees with the subject closer to it. "Teacher" is singular, so "was" is correct.
Quantitative
Find the error: "Each of the students have completed their assignment."
"Each" is singular, so "has" should be used instead of "have", and "his or her" instead of "their".
Verbal
Choose correctly spelled word:
Correct spelling is Necessary.
Quantitative
A and B invest ₹5,000 and ₹7,000 respectively in a business. After 6 months, A withdraws ₹2,000. If the profit at the end of the year is ₹4,500, find B's share.
A's investment: 5000 × 6 + 3000 × 6 = 30,000 + 18,000 = 48,000 B's investment: 7000 × 12 = 84,000 Ratio = 48,000 : 84,000 = 4 : 7 B's share = 7/(4+7) × 4500 = 7/11 × 4500 = ₹2,863.64
Reasoning
Statements: 1) Some boxes are cars, 2) Some cars are roads Conclusions: I) Some roads are boxes, II) Some cars are boxes, III) No box is a road, IV) Some roads are cars.
Correct answer: Only II and IV follow
Reasoning
Find the next number: 1, 3, 6, 10, 15, ?
Correct answer: 21
Verbal
A person who speaks many languages is a:
Polyglot speaks several languages.
Reasoning
A walks 10m North, turns right walks 5m, turns right walks 10m. Direction from start?
Correct answer: East (5m east of starting point)
Quantitative
A 120 m train crosses a pole in 8 s. Speed in km/h is:
Speed = 120/8 = 15 m/s = 54 km/h.
Reasoning
Number Series - 37, 47, 58, ?, 79, 95
Correct answer: 70
Verbal
He _____ to school every day.
Singular present.
Quantitative
A number is first increased by 25% and then decreased by 20%. Find the net percentage change.
Let number = 100 After 25% increase: 100 + 25 = 125 After 20% decrease: 125 - 20% of 125 = 125 - 25 = 100 Net change = 0%
Reasoning
Find the next number: 5, 10, 20, 40, ?
×2 each → 80.
Quantitative
The ratio of the ages of two persons is 4:3. After 6 years, the ratio becomes 9:7. What are their present ages?
Let present ages be 4x and 3x After 6 years: (4x + 6)/(3x + 6) = 9/7 7(4x + 6) = 9(3x + 6) 28x + 42 = 27x + 54 x = 12 Present ages: 4×12 = 48 years, 3×12 = 36 years
Your score
0/15(0%)
| Section | What shows up | Prep focus |
|---|---|---|
| Technical / domain | Syllabus aligned to the notification | Topic checklist |
| Aptitude | Quant + reasoning | Speed with accuracy |
| Interview | Subject depth + projects | Clear fundamentals |
First round: IOCL GATE-based Recruitment
Skills emphasized: GATE technical, GD/Interview
Languages: N/A for core
These are practice-style questions aligned to patterns students report for IOCL drives around 2026. They are not leaked live papers. Work them timed, then read the solutions only after you have an answer.
Problem: A number is increased by 20% and then decreased by 20%. What is the net percentage change?
Solution: Start with 100 → 120 → 96. Net change = 4% decrease. Formula: successive +a then −a gives −(a²/100)% = −4%.
Answer: 4% decrease
Problem: If the price of an item rises by 25%, by what percent should consumption fall so that expenditure stays the same?
Solution: Required reduction = r/(100+r) × 100 with r = 25. = 25/125 × 100 = 20%.
Answer: 20%
Problem: An article is marked 40% above cost and sold after a 10% discount. Find the profit percent.
Solution: SP = CP × 1.4 × 0.9 = 1.26 CP. Profit = 26%.
Answer: 26%
Problem: An article sold at 10% loss would give 5% profit if sold for ₹60 more. Find the cost price.
Solution: 0.9P + 60 = 1.05P 60 = 0.15P P = 60 / 0.15 = ₹400.
Answer: ₹400
Problem: Eight workers finish a job in 10 days. How many days will 10 workers take for the same job (same pace)?
Solution: Total man-days = 8 × 10 = 80. Days for 10 workers = 80 / 10 = 8 days.
Answer: 8 days
Problem: A vehicle travels at 60 km/h for 2.5 hours. How far does it go?
Solution: Distance = speed × time = 60 × 2.5 = 150 km.
Answer: 150 km
Problem: If two ratios are 3:5 and 5:7, what is the compound ratio?
Solution: Compound ratio = (3/5) × (5/7) = 3/7, written as 3:7.
Answer: 3:7
Problem: Find simple interest on ₹5000 at 8% per annum for 3 years.
Solution: SI = 5000 × 8 × 3 / 100 = ₹1200.
Answer: ₹1200
Problem: A person walks 5 km north, then 3 km east, then 5 km south. How far is he from the start, and in which direction?
Solution: North 5 and south 5 cancel. He is 3 km east of the start.
Answer: 3 km east
Problem: Find the next number: 3, 9, 27, 81, ?
Solution: Each term is multiplied by 3. Next = 81 × 3 = 243.
Answer: 243
Problem: Five friends sit in a row. A is to the left of B but right of C. D is to the right of B and left of E. Who is in the middle?
Solution: Order from left to right: C, A, B, D, E. The middle seat is B.
Answer: B
Problem: Book is to Reading as Fork is to ?
Solution: A book is used for reading; a fork is used for eating.
Answer: Eating
Problem: Given the root of a binary tree, return the level-order traversal (breadth-first) as a list of levels.
Approach: Use a queue. For each level, drain the current queue size, collect values, and enqueue children for the next level.
Complexity: O(n) time, O(n) space
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Given coin denominations and an amount, return the fewest coins needed to make that amount, or -1 if it is impossible.
Approach: Unbounded knapsack DP: let dp[x] be the minimum coins for amount x. For each coin, update dp[c..amount]. Initialize dp[0] = 0 and the rest to a large sentinel.
Complexity: O(amount × coins)
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Given a sorted array of distinct integers and a target, return the index of target or -1 if missing.
Approach: Maintain lo/hi. Compare mid with target and shrink the half that cannot contain it. Careful with overflow-free mid and empty arrays.
Complexity: O(log n) time
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Move all zeros in an array to the end while keeping the relative order of non-zero elements.
Approach: Two pointers: write non-zeros toward the front, then fill the remainder with zeros. Or swap zeros as you scan.
Complexity: O(n) time, O(1) space
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Rotate an array to the right by k steps. Example: [1,2,3,4,5,6,7], k = 3 → [5,6,7,1,2,3,4].
Approach: Normalize k %= n. Reverse the whole array, reverse the first k elements, then reverse the rest. That yields the rotation in place.
Complexity: O(n) time, O(1) space
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Find the first non-repeating character in a string and return its index, or -1 if none exists.
Approach: Count frequencies in one pass (hash map or array of 26 for lowercase). Second pass returns the first index with count 1.
Complexity: O(n) time
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Design a stack that supports push, pop, top, and getMin in average O(1) time.
Approach: Keep a parallel min-stack (or store pairs). When pushing, also push the new minimum. When popping, pop both stacks.
Complexity: O(1) per operation amortized
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Problem: Given an integer array, find the contiguous subarray with the largest sum and return that sum. Example: [-2,1,-3,4,-1,2,1,-5,4] → 6 (from [4,-1,2,1]).
Approach: Keep a running sum. If the running sum drops below 0, reset it to 0 before taking the next element (or track the best ending-here value). Track the global maximum as you scan once from left to right.
Complexity: O(n) time, O(1) extra space
IOCL tip: Restate the problem, sketch a brute-force idea, then tighten it. Call out edge cases (empty input, single element, overflow) before you write code.
Students usually say the first round is time-tight - easy marks vanish if you sit too long on one hard question. For IOCL, skim the paper in a couple of minutes, mark what you can finish cleanly, and protect accuracy. Languages people commonly use: N/A for core.
| Area | Why it matters at IOCL |
|---|---|
| GATE technical | What usually helps you clear the first round |
| Core CS (OOPs / DBMS / OS) | Technical interview depth |
| Oil Refining & Marketing PSU awareness | Helps in managerial / HR conversations |
| Communication | Explain your approach clearly; keep a few real examples ready for HR |