ONGC 2024 aptitude
Quantitative, reasoning, and verbal drills with solutions
ONGC Placement Papers 2024
Overview
This page collects ONGC placement papers from 2024 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 ONGC patterns and recent shifts.
Download / jump links
ONGC 2024 coding
DSA practice aligned to ONGC online assessments
ONGC interview experience
Round structure and tips from student reports
ONGC prep guide
Study plan and weekly schedule
ONGC Aptitude Mock Quiz
Timed placement-style MCQs with score and explanations after you submit. Use it to check speed and accuracy before the real test.
Questions15
Time10 min
Quantitative
Pointing to a photograph, a man said, "She is the daughter of my grandfather's only son." How is the man related to the person in the photograph?
Grandfather's only son = man's father Daughter of man's father = man's sister So the person is the man's sister
Quantitative
The average of 5 numbers is 20. If one number is removed, the average becomes 18. Find the removed number.
Correct answer: 28
Reasoning
All roses are flowers. Some flowers fade quickly. Conclusion: All roses fade quickly.
Only some flowers.
Verbal
Identify the correctly spelled word:
Accommodate has double "c" and double "m".
Quantitative
If the perimeter of a rectangle is 60 cm and its length is twice its breadth, find the area of the rectangle.
Let breadth = x cm, length = 2x cm Perimeter = 2(length + breadth) = 2(2x + x) = 6x = 60 x = 10 cm Length = 20 cm, Breadth = 10 cm Area = 20 × 10 = 200 cm²
Verbal
Choose the correct synonym for "Ephemeral":
"Ephemeral" means lasting for a very short time, temporary. "Temporary" is the synonym.
Reasoning
Odd one out: 121, 144, 169, 196, 225
Others are odd squares.
Quantitative
A, B, and C can complete a work in 10, 15, and 20 days respectively. If they work together, in how many days will they complete the work?
Correct answer: 4.62 days
Reasoning
A person walks 5 km north, then 3 km east, then 2 km south. How far and in which direction is he from the starting point?
Net north = 5 - 2 = 3 km Net east = 3 km Distance = √(3² + 3²) = √18 = 3√2 km Direction = Northeast
Verbal
Problem: "She is good _____ mathematics." a) at b) in c) on d) with
"Good at" is the correct prepositional phrase for skills.
Verbal
Synonym of "Meticulous":
Meticulous means detailed.
Reasoning
Odd one out: 8, 27, 64, 100, 125
Others are perfect cubes; 100 is not.
Reasoning
Odd one out: Triangle, Square, Circle, Rectangle
Circle has no straight sides.
Quantitative
Reading Comprehension - Main Idea (2025)
Correct answer: Renewable energy and its growing importance
Quantitative
If 3x + 5 = 20, then x equals:
3x = 15 → x = 5.
Your score
0/15(0%)
Review
ONGC exam pattern 2024
| 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: ONGC GATE-based Recruitment
Skills emphasized: GATE technical, interview
Languages: N/A for core
Sample ONGC questions with solutions
These are practice-style questions aligned to patterns students report for ONGC drives around 2024. They are not leaked live papers. Work them timed, then read the solutions only after you have an answer.
Quantitative aptitude (2024)
Q1: CI vs SI hint
Problem: Find compound interest on ₹10,000 at 10% per annum for 2 years, compounded annually.
Solution: Amount = 10000 × (1.1)² = 10000 × 1.21 = ₹12,100. CI = 12100 − 10000 = ₹2100. (SI for same period would be ₹2000; the extra ₹100 is interest on first-year interest.)
Answer: ₹2100
Q2: Clock angle
Problem: What is the angle between the hour and minute hands at 3:00?
Solution: At 3:00 the hands are exactly 90° apart (one quarter of the circle).
Answer: 90°
Q3: Permutation basic
Problem: In how many ways can 5 different books be arranged on a shelf?
Solution: Arrangements of 5 distinct items = 5! = 120.
Answer: 120
Q4: Consecutive integers
Problem: If the sum of three consecutive integers is 72, what is the smallest of these integers?
Solution: Let the integers be x, x+1, and x+2.
x + (x+1) + (x+2) = 72 3x + 3 = 72 3x = 69 x = 23
So the integers are 23, 24, and 25.
Answer: 23
Q5: Train and pole
Problem: A train 150 meters long passes a pole in 15 seconds. What is its speed in km/h?
Solution: Distance = 150 m = 0.15 km. Time = 15 s = 15/3600 h = 1/240 h. Speed = 0.15 ÷ (1/240) = 0.15 × 240 = 36 km/h.
Faster check: 150/15 = 10 m/s → 10 × 18/5 = 36 km/h.
Answer: 36 km/h
Q6: Profit on a pen
Problem: If the cost price of a pen is ₹40 and it is sold at a 25% profit, what is the selling price?
Solution: Profit = 25% of 40 = ₹10. Selling price = 40 + 10 = ₹50.
Or SP = CP × 1.25 = 40 × 1.25 = ₹50.
Answer: ₹50
Q7: A and B together
Problem: A can finish a job in 10 days and B in 20 days. How long will they take working together?
Solution: A’s one-day work = 1/10. B’s one-day work = 1/20. Together = 1/10 + 1/20 = 3/20 per day. Time = 20/3 ≈ 6.67 days (6 days 16 hours).
Answer: 20/3 days
Q8: Sum of naturals
Problem: What is the sum of the first 50 natural numbers?
Solution: Sum of first n naturals = n(n+1)/2. For n = 50: 50 × 51 / 2 = 1275.
Answer: 1275
Logical reasoning (2024)
Q1: Coding letter shift
Problem: If CAT is coded as DBU, how is DOG coded in the same way?
Solution: Each letter moves +1 in the alphabet: C→D, A→B, T→U. D→E, O→P, G→H → EPH.
Answer: EPH
Q2: Blood relation
Problem: Pointing to a photograph, Ravi says, ‘She is the daughter of my mother’s only son.’ How is the girl related to Ravi?
Solution: Ravi’s mother’s only son is Ravi himself (assuming one son). The girl is therefore Ravi’s daughter.
Answer: Daughter
Q3: Syllogism
Problem: Statements: All engineers are graduates. Some graduates are managers. Conclusion: Some engineers are managers. Does it follow?
Solution: The ‘some graduates’ who are managers need not overlap with the engineers. The conclusion does not follow necessarily.
Answer: Does not follow
Q4: Direction turn
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
Coding practice (2024)
Coding Q1: First unique character
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
ONGC 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.
Coding Q2: Stack with min
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
ONGC 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.
Coding Q3: Maximum subarray sum (Kadane)
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
ONGC 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.
Coding Q4: Reverse a string in place
Problem: Given a mutable character array representing a string, reverse it in place without allocating another array of the same size.
Approach: Use two pointers at the start and end. Swap characters, then move inward until the pointers meet. Watch empty and single-character inputs.
Complexity: O(n) time, O(1) extra space
ONGC 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.
Coding Q5: Check prime
Problem: Write a function that returns true if n is prime and false otherwise. Handle n < 2 correctly.
Approach: Return false for n < 2. Trial-divide from 2 to floor(sqrt(n)). If any divisor divides n evenly, it is composite; otherwise prime.
Complexity: O(√n) time
ONGC 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.
Coding Q6: Valid parentheses
Problem: Given a string containing only ‘()[]’, decide whether the brackets are balanced and correctly nested.
Approach: Scan left to right with a stack. Push opening brackets. On a closing bracket, the stack top must be the matching opener. At the end the stack must be empty.
Complexity: O(n) time, O(n) space
ONGC 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.
Coding Q7: Two Sum
Problem: Given an array of integers and a target, return indices of two numbers that add up to the target. Assume exactly one solution and you may not use the same element twice.
Approach: Walk the array once. For each value x, check whether target − x was seen earlier in a hash map of value → index. If yes, return both indices; else store x.
Complexity: O(n) time, O(n) space
ONGC 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.
Coding Q8: Longest substring without repeating characters
Problem: Given a string s, find the length of the longest substring without repeating characters. Example: ‘abcabcbb’ → 3 (‘abc’).
Approach: Sliding window with a map (or last-seen index) of characters. Expand the right pointer; when a duplicate appears inside the window, move the left pointer past the previous occurrence.
Complexity: O(n) time
ONGC 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.
Deep prep notes for ONGC
How the ONGC gate-based recruitment usually feels
Students usually say the first round is time-tight - easy marks vanish if you sit too long on one hard question. For ONGC, 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.
Topic weight hints
| Area | Why it matters at ONGC |
|---|---|
| GATE technical | What usually helps you clear the first round |
| Core CS (OOPs / DBMS / OS) | Technical interview depth |
| Oil & Gas Exploration PSU awareness | Helps in managerial / HR conversations |
| Communication | Explain your approach clearly; keep a few real examples ready for HR |
14-Day sprint
- Days 1-3: Learn the 2024 pattern and take two sectional mocks
- Days 4-7: Closed practice on weak topics from your error log
- Days 8-10: Full mocks every other day; review the same day
- Days 11-14: Practice explaining projects out loud, light revision, sleep and IDs ready