Palindromic Series

Palindromic Series problems consist of numbers that read the same forwards and backwards (e.g., 11, 22, 33, 101, 111, 121). These problems test your knowledge of palindromic numbers and ability to identify them in sequence.

10Worksheets
200+Practice Questions
IntermediateDifficulty
1-2 hoursHours to Master

Introduction to Palindromic Series

Palindromic Series problems consist of numbers that read the same forwards and backwards (e.g., 11, 22, 33, 101, 111, 121). These problems test your knowledge of palindromic numbers and ability to identify them in sequence.

Prerequisites

Understanding of palindromic numbers Number reversal concept Digit manipulation Pattern recognition
Why This Matters: Palindromic Series problems appear in 0-1 questions in advanced exams. They test number pattern recognition.

How to Solve Palindromic Series Problems

1

Step 1: List palindromic numbers in increasing order: 1-9, 11,22,33,44,55,66,77,88,99,101,111,121,...

2

Step 2: Compare given sequence with the list of palindromes

3

Step 3: Identify the pattern (consecutive palindromes, every other, specific digit patterns)

4

Step 4: For next term: find the next palindrome after the last term

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Step 5: Verify that all terms are palindromic numbers

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Step 6: Present the next term

Pro Strategy: A palindromic number reads the same forwards and backwards. For two-digit numbers, palindromes are 11,22,33,...,99. For three-digit numbers, palindromes are 101,111,121,131,...,191,202,...

Example Problem

Example: Find the next term in the sequence: 11, 22, 33, 44, 55, ___ Solution: Step 1: Palindromes: 11,22,33,44,55,66,77,... Step 2: Sequence is consecutive two-digit palindromes Step 3: Next palindrome = 66 Answer: 66

Pro Tips & Tricks

  • One-digit palindromes: 1-9 (all digits)
  • Two-digit palindromes: 11,22,33,44,55,66,77,88,99
  • Three-digit palindromes: 101,111,121,131,141,151,161,171,181,191,202,...
  • Four-digit palindromes: 1001,1111,1221,1331,1441,1551,1661,1771,1881,1991,2002,...
  • To check if a number is palindrome: reverse its digits and compare
  • Palindromes can have odd or even number of digits

Shortcut Methods to Solve Faster

Next palindrome = smallest palindrome greater than last term
For two-digit palindromes, digits are the same (aa)
For three-digit palindromes, first and last digits are the same (aba)
Palindromes are symmetric around the center

Common Mistakes to Avoid

Including numbers like 10, 12 as palindromes (they are not)
Forgetting that single-digit numbers are palindromes
Missing palindromes like 101 after 99
Not recognizing that 0 is a palindrome (but rarely used)

Exam Importance

Palindromic Series is an important topic for various competitive exams. Here's how frequently it appears:

SSC CGL
0-1 questions
BANKING PO
0-1 questions
RAILWAYS RRB
0-1 questions
CAT
0-1 questions
GMAT
0-1 questions
INSURANCE
0-1 questions

Ready to Master Palindromic Series?

Start with Worksheet 1 and work your way up to expert level! Each worksheet includes:

20 practice questions
Detailed solutions
Step-by-step explanations
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