ISRO Placement Papers 2024

Overview

This page collects ISRO placement papers from 2024 with previous-year questions, solutions, and the 2024 exam pattern. It is useful when you want real drive history: what the OA looked like, which question types repeated, and how solutions were approached. Work through the papers below to build speed and accuracy, then compare against newer 2025 material so your prep matches both established ISRO patterns and the latest shifts.

2024 Pattern

The 2024 ISRO placement process emphasized technical knowledge, space technology concepts, and engineering fundamentals. Written examination included technical and aptitude questions.

ISRO written examination 2024 pattern

Section	Questions	Time	Difficulty
Technical	40-50	60 min	Medium-Hard
Aptitude	20-25	30 min	Medium

ISRO Placement Papers 2024 - actual questions & solutions

This section contains practice questions styled on ISRO placement papers 2024 (previous-year pattern), with worked solutions. Use them as timed sectional drills - from student reports drives vary by college and role, so treat this as a high-signal practice bank, not an official paper dump.

Question 1

Q1: Pipe A fills a tank in 10 hours, pipe B in 15 hours. How long to fill together?

Solution:

Combined rate = 1/10 + 1/15 = (10+15)/(10×15). Time = 10×15/(10+15) = 6 hours.

Answer: 6 hours

Question 2

Q2: The ratio of ages of A and B is 3:5. After 10 years, the ratio becomes 5:7. Find A’s present age.

Solution:

Let ages be 3x and 5x.

(3x + 10)/(5x + 10) = 5/7 7(3x + 10) = 5(5x + 10) 21x + 70 = 25x + 50 x = 5 A’s age = 3×5 = 15 years.

Answer: 15 years

Question 3

Q3: A number is increased by 10% and then decreased by 10%. Find the net percentage change.

Solution:

Let original = 100. After +10% → 110. After −10% → 110 − 11 = 99.

Net change = 100 − 99 = 1. Net % = 1% decrease (always a loss of (10/10)² %).

Answer: 1% decrease

Question 4

Q4: A train 180 m long crosses a pole in 12 seconds. Find its speed in km/h.

Solution:

Speed = distance/time = 180/12 m/s = (180/12) × (18/5) = 54 km/h.

Answer: 54 km/h

Question 5

Q5: Pointing to a photo, Ravi said, ‘He is the son of my grandfather’s only son.’ How is the person related to Ravi?

Solution:

Grandfather’s only son = Ravi’s father. Son of Ravi’s father = Ravi himself (or his brother).

In standard puzzle framing with one son implied for the speaker context: the person is Ravi’s brother (or Ravi). Most campus keys take Brother.

Answer: Brother

Question 6

Q6: Which number does not belong: 2, 3, 6, 7, 8, 14?

Solution:

Pattern: Pairs (2,3)(6,7) then 8 breaks; or primes vs composites - common key 8 (only even composite in a mixed set framed as n,n+1 pairs)

Odd one out = 8.

Answer: 8

Question 7

Q7: In OOP, hiding internal details and showing only essential features is called?

Solution:

This is the definition of Encapsulation (often paired with abstraction in interviews).

Answer: Encapsulation

Question 8

Q8: Which normal form removes transitive dependency?

Solution:

1NF: atomic values. 2NF: no partial dependency. 3NF: no transitive dependency.

Answer: 3NF

Question 9: rotate array right by k

Show solution

Problem Statement: Rotate the array to the right by k steps.

Example:

Input: [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]

Solution (Java):

public void rotate(int[] nums, int k) {
    k %= nums.length;
    reverse(nums, 0, nums.length - 1);
    reverse(nums, 0, k - 1);
    reverse(nums, k, nums.length - 1);
}
void reverse(int[] a, int l, int r) {
    while (l < r) { int t = a[l]; a[l++] = a[r]; a[r--] = t; }
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 10: maximum subarray sum

Show solution

Problem Statement: Find the contiguous subarray with the largest sum.

Example:

Input: [-2, 1, -3, 4, -1, 2, 1, -5, 4]
Output: 6  // [4, -1, 2, 1]

Solution (Java):

public int maxSubArray(int[] nums) {
    int best = nums[0], cur = nums[0];
    for (int i = 1; i < nums.length; i++) {
        cur = Math.max(nums[i], cur + nums[i]);
        best = Math.max(best, cur);
    }
    return best;
}

Time Complexity: O(n)
Space Complexity: O(1)

Question 11: check palindrome

Show solution

Problem Statement: Return true if the string reads the same forward and backward (ignore case).

Example:

Input: "Level"
Output: true

Solution (Java):

public boolean isPalindrome(String s) {
    s = s.toLowerCase();
    int i = 0, j = s.length() - 1;
    while (i < j) {
        if (s.charAt(i++) != s.charAt(j--)) return false;
    }
    return true;
}

Time Complexity: O(n)
Space Complexity: O(1)

Key insights from 2024 ISRO written examination

1. Technical Section is Critical: Must perform well in space technology and engineering fundamentals
2. Aptitude Section: Important for overall performance
3. Time Management: 40-50 technical questions in 60 min + 20-25 aptitude in 30 min
4. Success Rate: Only 10-15% cleared written exam and advanced to interviews
5. Platform: ISRO written examination
6. Focus Areas: Space technology, orbital mechanics, satellite systems, engineering fundamentals

ISRO 2024 interview experiences

Based on candidate experiences from 2024 ISRO interviews:

2024 Interview Process:

1. Written Examination (90 minutes): Technical (40-50) + Aptitude (20-25)
2. Technical Interview (60-90 minutes): Space technology concepts, orbital mechanics, satellite systems, engineering fundamentals, problem-solving
3. HR Interview (30-45 minutes): Behavioral questions, company fit, motivation, space technology passion

Common 2024 Interview Topics:

• Technical: Space technology, orbital mechanics, satellite systems, engineering fundamentals
• Aptitude: Quantitative reasoning, logical reasoning
• Behavioral: Problem-solving approach, space technology passion, teamwork, motivation

Success Tips:

• Strong technical performance is essential - master space technology and engineering fundamentals
• Understand orbital mechanics and satellite systems
• Practice problem-solving in space technology domain
• Prepare behavioral examples demonstrating space technology passion
• Understand ISRO’s missions and space technology programs
• Practice explaining complex technical concepts clearly

For detailed interview experiences, visit ISRO Interview Experience page.

Preparation tips for ISRO 2024 pattern

1. Master Technical Fundamentals: Focus on space technology, orbital mechanics, satellite systems - study thoroughly
2. Engineering Fundamentals: Strong understanding of engineering fundamentals relevant to space technology
3. Practice Previous Year Papers: Solve ISRO written exam papers from 2020-2024 to understand patterns
4. Time Management: Practice completing 40-50 technical questions in 60 minutes
5. Aptitude Practice: Practice quantitative and logical reasoning
6. Space Technology: Deep understanding of orbital mechanics, satellite systems, space missions
7. Problem-Solving: Practice solving complex technical problems in space technology domain
8. Behavioral Preparation: Prepare examples using STAR format - space technology passion, problem-solving
9. Mock Tests: Take timed practice tests to improve speed and accuracy
10. ISRO Missions: Stay updated with ISRO’s missions and space technology programs

Related resources

ISRO 2025 papers→

Latest ISRO placement papers with current year questions

ISRO technical questions→

Complete collection of ISRO technical problems

ISRO interview experience→

Real interview experiences from successful candidates

ISRO preparation guide→

Comprehensive preparation strategy for ISRO placement

ISRO main page→

Complete ISRO placement guide with eligibility, process, and salary

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Practice 2024 papers to understand ISRO pattern and prepare effectively!