If you are preparing for the RBI Assistant, IBPS, or other banking exams in 2025, learning how to solve wrong number series questions is important. These questions are common in both Prelims and Mains and test your ability to find mistakes in a pattern of numbers.
To support your number series practice, we have included 10 updated wrong number series questions with clear solutions. These questions follow the latest exam pattern and are meant to help you get familiar with the types of problems you may see in the actual exam
What is a Wrong Number Series?
A wrong number series is a type of question where a sequence of numbers is given, but one number in the series does not follow the correct pattern or logic. Your task is to find the number that doesn’t fit. These questions test your ability to identify patterns, such as addition, subtraction, multiplication, division, or a mix of these. They are commonly asked in banking exams to check your numerical reasoning skills.
Practice Wrong Number Series Questions Below
You can practice 10 updated wrong number series questions below. Each question comes with options, the correct answer, and a short explanation to help you understand the logic. Use these for regular number series practice to improve your speed and accuracy for upcoming banking exams.
1. Which number is wrong in the series?
3, 8, 15, 26, 35, 48, 63
a) 15
b) 26
c) 35
d) 48
e) 63
Correct Answer: b) 26
Solution:
Pattern: Add consecutive odd numbers →
3 (+5) = 8, 8 (+7) = 15, 15 (+9) = 24, 24 (+11) = 35, 35 (+13) = 48, 48 (+15) = 63
Given number is 26 instead of 24, so 26 is wrong.
2. Which number is wrong in the series?
100, 96, 89, 79, 66, 50, 35
a) 96
b) 89
c) 66
d) 50
e) 35
Correct Answer: e) 35
Solution:
Pattern: -4, -7, -10, -13, -16, -19
Last term should be 50 – 19 = 31, but 35 is given. So 35 is incorrect.
3. Which number is wrong in the series?
1, 4, 9, 16, 25, 37, 49
a) 25
b) 37
c) 16
d) 9
e) 49
Correct Answer: b) 37
Solution:
Pattern: Perfect squares → 1², 2², 3², 4², 5², 6², 7² = 49
The correct number should be 36 instead of 37.
4. Which number is wrong in the series?
7, 14, 29, 58, 115, 230
a) 14
b) 29
c) 58
d) 115
e) 230
Correct Answer: b) 29
Solution:
Pattern: ×2
7×2 = 14, 14×2 = 28 (but 29 is given), 28×2 = 56, and so on
So 29 is incorrect.
5. Which number is wrong in the series?
500, 250, 125, 60, 30, 15
a) 250
b) 125
c) 60
d) 30
e) 15
Correct Answer: c) 60
Solution:
Pattern: ÷2
500 ÷ 2 = 250, 250 ÷ 2 = 125, 125 ÷ 2 = 62.5
But 60 is given, so it’s wrong.
6. Which number is wrong in the series?
2, 5, 10, 17, 26, 37, 51
a) 10
b) 17
c) 26
d) 37
e) 51
Correct Answer: e) 51
Solution:
Pattern: Add odd numbers → +3, +5, +7, +9, +11, +13
37 + 13 = 50 expected, but 51 is given.
7. Which number is wrong in the series?
81, 72, 64, 56, 47, 41, 33
a) 64
b) 48
c) 41
d) 33
e) 47
Correct Answer: e) 47
Solution:
Pattern: -9, -8, -8, -8, -7, -8
56 – 8 = 48 is expected, but 47 is given. So 47 is incorrect.
8. Which number is wrong in the series?
2, 6, 18, 54, 162, 485
a) 18
b) 54
c) 162
d) 485
e) 6
Correct Answer: d) 485
Solution:
Pattern: ×3
162 × 3 = 486 expected, but 485 is given.
9. Which number is wrong in the series?
15, 31, 63, 127, 256, 511
a) 127
b) 63
c) 256
d) 511
e) 31
Correct Answer: c) 256
Solution:
Pattern: 2ⁿ – 1
2⁴ -1 = 15, 2⁵ -1 = 31, … 2⁸ -1 = 255 expected, but 256 is given.
10. Which number is wrong in the series?
91, 84, 77, 70, 64, 56, 49
a) 91
b) 70
c) 63
d) 64
e) 56
Correct Answer: d) 64
Solution:
Pattern: -7
70 – 7 = 63 expected, but 64 is given instead.
Government Banking Exams Online Course & Mock Tests
Mock tests help you see where you stand and improve your performance. They also get you comfortable with exam timing and format. At Oliveboard, our Free Banking Exams Mock Test 2025 course includes focused number series practice and wrong number series questions, along with all other key topics. You’ll get:
- Live classes covering basics to advanced concepts
- Regular mock tests that include solved number series practice sets
- Detailed solutions for wrong number series questions
- Study materials designed for RBI Assistant, IBPS, and other banking exams
Course Highlights
This course covers all major government banking exams, such as RBI Assistant, IBPS, SBI, and more. You will get step-by-step guidance on important topics, including number series practice and wrong number series questions. The course includes clear lessons, regular practice, and feedback to help you build a strong foundation.
- 100+ live classes to learn and understand concepts
- 25+ live practice sessions for hands-on problem solving
- Short, focused study material in every class
- Complete coverage of both Prelims and Mains syllabus for all banking exams
- Special sessions on general awareness for Mains
- Questions sorted into Easy, Medium, and Hard levels for each topic
- Live doubt-clearing classes to answer your questions
- 20+ Prelims mock tests to check your preparation
- 10+ Mains mock tests with detailed feedback
- High-level Data Interpretation tests (10) and Reasoning tests (10)
- English practice tests (15) for reading, grammar, and comprehension
- General Knowledge tests (120) to stay updated on current affairs
- Sectional tests (60) for each topic in detail
- Topic-wise tests (99) for focused revision
Wrong Number Series for Banking Exams Frequently Asked Questions (FAQs)
Ans. It’s a type of reasoning question where one number in a sequence is incorrect, and you have to find the one that breaks the logical pattern.
Ans. They test your pattern recognition and speed, which are key skills in both Prelims and Mains exams like IBPS and RBI Assistant.
Ans. Look for common patterns such as addition, subtraction, multiplication, division, or squares and cubes.
Ans. They appear in both stages of banking exams and are especially common in the reasoning or quantitative aptitude sections.
Ans. Yes, platforms like Oliveboard offer live classes, practice sets, and mock tests that include number series and wrong number series practice.
Ans. Common patterns include arithmetic, geometric, alternating sequences, prime numbers, squares, and cubes.
Ans. Not necessarily. You need good observation skills, pattern recognition, and regular practice more than memorized formulas.
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