Sequence and Series Questions for CAT: 30 Practice Questions + Free PDF Download

Overview: Sequence and series questions for CAT are an important part of the Quantitative Aptitude section. These questions check how well a student can identify number patterns, apply formulas, and solve logic-based numerical problems.

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In the CAT exam, this topic can appear directly or in combination with algebra, number system, and arithmetic. Practicing all CAT questions of sequences and series can help aspirants improve speed, accuracy, and confidence.

What You Will Get in This Blog

This blog covers the basic concepts, formulas, types of questions, and 25+ practice questions on sequence and series for CAT preparation.

You will also understand how to prepare this topic using mocks and mock test series, previous year question paper practice, and topic-wise revision.

Key Takeaways

• Sequence and series is an important topic in the CAT syllabus.
• Questions are usually based on patterns, AP, GP, HP, and special series.
• Regular practice of cat questions improves speed and accuracy.
• Solving cat important questions helps in better exam preparation.
• Mock tests and previous year question paper analysis are useful for revision.

Table of Contents

1. What are Sequence and Series Questions for CAT?
2. Importance of Sequence and Series Questions for CAT
3. Important Concepts of Sequence and Series for CAT
4. Important Formulas for Sequence and Series CAT Questions
5. Types of Sequence and Series Questions for CAT
6. Sequence and Series Questions for CAT Practice Set
7. Tips to Solve Sequence and Series CAT Questions
8. Common Mistakes to Avoid
9. Best Resources to Practice Sequence and Series for CAT
10. Conclusion

What are Sequence and Series Questions for CAT?

Sequence and Series questions for CAT are based on ordered numbers that follow a fixed rule or pattern. A sequence is a list of numbers arranged in a specific order, while a series is the sum of the terms of a sequence.

For example, 2, 4, 6, 8, 10 is a sequence because the numbers follow a pattern of adding 2. The sum 2 + 4 + 6 + 8 + 10 is a series.

This topic is included in the CAT syllabus and is often tested through direct pattern-based questions or formula-based problems.

Download CAT Sequence and Series Questions PDF 

Importance of Sequence and Series Questions for CAT

Sequence and series questions for CAT are important because they help students build logical thinking and numerical ability. These questions can be solved quickly if the student understands the pattern clearly.

In the CAT exam, even one correct question can make a difference in percentile. That is why students should practice cat important questions from this topic regularly.

Important Concepts of Sequence and Series for CAT

Before solving all CAT questions of sequences and series, students should understand the core concepts of this topic.

• Arithmetic Progression
• Geometric Progression
• Harmonic Progression
• Special number series
• Squares and cubes series
• Fibonacci series
• Mixed pattern series
• Alternate term series

Important Formulas for Sequence and Series CAT Questions

The table below covers some basic formulas that are useful while solving sequence and series questions for CAT. You can get best free resources by Supergrads too for the practice.

Students should revise these formulas regularly before attempting mocks and mock test series.

Concept	Formula	Use
nth term of AP	an = a + (n - 1)d	Used to find any term in an arithmetic progression
Sum of AP	Sn = n/2 [2a + (n - 1)d]	Used to find the sum of terms in AP
nth term of GP	an = ar^(n - 1)	Used to find any term in a geometric progression
Sum of GP	Sn = a(r^n - 1)/(r - 1)	Used to find the sum of terms in GP
Sum of first n natural numbers	n(n + 1)/2	Used in basic series questions
Sum of squares	n(n + 1)(2n + 1)/6	Used in square-based series questions
Sum of cubes	[n(n + 1)/2]^2	Used in cube-based series questions

Types of Sequence and Series Questions for CAT

Different types of cat questions can be asked from sequence and series. Students should practice each type separately before moving to mixed practice.

These question types are also useful while revising CAT important questions and previous year question paper sets. Check with the CAT official mock test to understand the types of questions asked.

Question Type	What It Tests
Missing term questions	Ability to identify patterns
Next term questions	Logical continuation of a sequence
AP-based questions	Use of common difference
GP-based questions	Use of common ratio
Sum-based questions	Application of series formulas
Mixed pattern questions	Advanced pattern recognition

Sequence and Series Questions for CAT Practice Set

Here are 30 sequence and series questions for CAT preparation. These questions include easy, moderate, and slightly advanced patterns.

Students should solve these questions before checking the answers to improve accuracy and exam-level thinking.

Q1. Find the next term: 2, 5, 8, 11, 14, ?

A) 15
B) 16
C) 17
D) 18

Answer: C) 17

Q2. Find the next term: 3, 6, 12, 24, ?

A) 36
B) 48
C) 60
D) 72

Answer: B) 48

Q3. What is the 15th term of AP: 5, 8, 11, 14, ...?

A) 44
B) 47
C) 50
D) 52

Answer: B) 47

Q4. Find the sum of first 20 natural numbers.

A) 190
B) 200
C) 210
D) 220

Answer: C) 210

Q5. Find the next term: 1, 4, 9, 16, 25, ?

A) 30
B) 35
C) 36
D) 49

Answer: C) 36

Q6. Find the next term: 2, 6, 12, 20, 30, ?

A) 40
B) 42
C) 44
D) 46

Answer: B) 42

Q7. Find the next term: 1, 2, 6, 24, 120, ?

A) 600
B) 720
C) 840
D) 960

Answer: B) 720

Q8. Find the 10th term of GP: 2, 4, 8, 16, ...

A) 512
B) 1024
C) 2048
D) 4096

Answer: B) 1024

Q9. Find the next term: 7, 14, 28, 56, ?

A) 84
B) 98
C) 112
D) 120

Answer: C) 112

Q10. Find the sum: 1 + 2 + 3 + ... + 50

A) 1225
B) 1250
C) 1275
D) 1300

Answer: C) 1275

Q11. Find the next term: 1, 3, 6, 10, 15, ?

A) 18
B) 20
C) 21
D) 24

Answer: C) 21

Q12. Find the next term: 64, 32, 16, 8, ?

A) 2
B) 4
C) 6
D) 8

Answer: B) 4

Q13. Find the next term: 5, 10, 17, 26, 37, ?

A) 48
B) 49
C) 50
D) 52

Answer: C) 50

Q14. Find the next term: 1, 8, 27, 64, ?

A) 100
B) 121
C) 125
D) 144

Answer: C) 125

Q15. Find the next term: 13, 21, 34, 55, ?

A) 76
B) 81
C) 89
D) 91

Answer: C) 89

Q16. Find the sum of first 10 odd numbers.

A) 80
B) 90
C) 100
D) 110

Answer: C) 100

Q17. Find the next term: 2, 3, 5, 8, 13, ?

A) 18
B) 20
C) 21
D) 24

Answer: C) 21

Q18. Find the next term: 81, 27, 9, 3, ?

A) 0
B) 1
C) 2
D) 3

Answer: B) 1

Q19. Find the next term: 10, 20, 35, 55, 80, ?

A) 100
B) 105
C) 110
D) 115

Answer: C) 110

Q20. Find the next term: 4, 9, 19, 39, 79, ?

A) 149
B) 159
C) 169
D) 179

Answer: B) 159

Q21. Find the 20th term of AP: 2, 5, 8, 11, ...

A) 56
B) 57
C) 58
D) 59

Answer: D) 59

Q22. Find the next term: 2, 4, 7, 11, 16, ?

A) 20
B) 21
C) 22
D) 24

Answer: C) 22

Q23. Find the next term: 3, 9, 27, 81, ?

A) 162
B) 216
C) 243
D) 324

Answer: C) 243

Q24. Find the next term: 1, 1, 2, 3, 5, 8, ?

A) 11
B) 12
C) 13
D) 15

Answer: C) 13

Q25. Find the next term: 11, 22, 44, 88, ?

A) 132
B) 154
C) 176
D) 198

Answer: C) 176

Q26. Find the next term: 100, 90, 72, 48, ?

A) 20
B) 24
C) 28
D) 30

Answer: A) 20

Q27. Find the next term: 6, 11, 21, 41, 81, ?

A) 141
B) 151
C) 161
D) 171

Answer: C) 161

Q28. Find the next term: 2, 5, 10, 17, 26, ?

A) 35
B) 36
C) 37
D) 38

Answer: C) 37

Q29. Find the next term: 9, 18, 36, 72, ?

A) 108
B) 126
C) 144
D) 162

Answer: C) 144

Q30. Find the next term: 1, 4, 13, 40, 121, ?

A) 242
B) 302
C) 344
D) 364

Answer: D) 364

Download CAT Quantitative Aptitude Questions PDF

Tips to Solve Sequence and Series CAT Questions

Sequence and series questions for CAT become easier when students follow a structured approach. Instead of guessing the pattern randomly, check the difference, ratio, squares, cubes, and alternate positions.

These tips are also useful while solving cat questions in sectional tests, mocks and mock test series.

Tip	How It Helps
Check the difference between terms	Helps identify arithmetic progression and second-level patterns
Check the ratio between terms	Useful for geometric progression questions
Look for squares and cubes	Many number series questions are based on square and cube patterns
Observe alternate terms	Some questions have two different patterns running together
Do not spend too much time	If the pattern is not clear within a minute, move ahead and return later
Practice through mock tests	Improves speed, accuracy, and exam temperament

Common Mistakes to Avoid

Many students lose marks in sequence and series because they rush into calculations without understanding the pattern. A careful approach can help avoid these mistakes.

• Assuming every question is based on AP or GP
• Not checking alternate terms
• Ignoring second and third differences
• Not revising basic formulas
• Spending too much time on one difficult question
• Skipping previous year question paper practice

Download Free TITA Questions PDF Asked in CAT

Best Resources to Practice Sequence and Series for CAT

To master sequence and series questions for CAT, students should use a mix of concept notes, practice sets, topic-wise tests, and mocks.

• CAT syllabus for understanding the complete Quant section
• CAT eligibility details before starting the admission journey
• CAT exam pattern for knowing section-wise structure
• CAT important questions for topic-wise revision
• Mocks and mock test series for exam-level practice
• Previous year question paper sets for understanding actual exam trends
• CAT questions from reliable preparation resources

Conclusion

Sequence and Series questions for CAT are scoring if practiced with the right method. Students should first understand the concepts, revise formulas, and then solve different types of questions regularly.

Practicing all CAT questions of sequences and series, attempting mocks and mock test series, and analyzing previous year question paper sets can help students improve accuracy and confidence for the CAT exam.