All Exams Test series for 1 year @ ₹349 only
Question

Consider the sequence AB_CC_A_BCCC_BBC_C that follows a certain pattern. Which one of the following completes the sequence?

The correct answer is

B, C, B, A, C

Analyzing the Sequence Pattern

The given sequence is AB_CC_A_BCCC_BBC_C. This is a letter series with missing characters, and we need to find the correct set of characters from the options to complete the sequence following a specific pattern.

The sequence has blanks at positions 3, 6, 8, 13, and 17:

A B   C C    A    B C C C    B B C    C

There are 5 blanks, and the options provide 5 letters to fill these blanks in order.

Testing the Options

Let's try filling the blanks with the letters from each option and look for a repeating pattern in the resulting sequence.

Testing Option 1: B, C, B, C, A

Filling the blanks:

A B B C C C A B B C C C C B B C A C

Resulting sequence: ABBCCCABBCCCCBBCAC

Let's look for repeating segments. This sequence doesn't immediately show a clear, consistent repeating block.

Testing Option 2: A, C, B, C, A

Filling the blanks:

A B A C C C A B B C C C C B B C A C

Resulting sequence: ABACCCABBCCCCBBCAC

This sequence also does not show a clear, consistent repeating block.

Testing Option 3: B, C, B, A, C

Filling the blanks:

A B B C C C A B B C C C A B B C C C

Resulting sequence: ABBCCCABBCCCABBCCC

Let's examine this sequence closely:

ABBCCC | ABBCCC | ABBCCC

This sequence is formed by repeating the block "ABBCCC" exactly three times.

Identifying the Pattern

The sequence formed by filling the blanks with B, C, B, A, C is ABBCCCABBCCCABBCCC. This sequence clearly follows a repeating pattern of the group of letters "ABBCCC".

Let's verify this against the original sequence structure:

Original: A B    C C    A    B C C C    B B C    C

Pattern:     A B  B  C C  C  A  B  B C C C  A  B B C  C  C

The letters from Option 3 (B, C, B, A, C) fit perfectly into the blank positions to complete the "ABBCCC" repeating pattern.

Blank 1 (Position 3) is filled by the 3rd letter of the pattern (B).

Blank 2 (Position 6) is filled by the 6th letter of the pattern (C).

Blank 3 (Position 8) is filled by the 2nd letter of the pattern's second repetition (B).

Blank 4 (Position 13) is filled by the 1st letter of the pattern's third repetition (A).

Blank 5 (Position 17) is filled by the 5th letter of the pattern's third repetition (C).

Therefore, the sequence B, C, B, A, C correctly completes the sequence.

Conclusion

By filling the blanks with the letters from Option 3 (B, C, B, A, C), the sequence becomes ABBCCCABBCCCABBCCC, which demonstrates a clear repeating pattern of "ABBCCC". This is the correct set of letters that completes the sequence.

Revision Table: Sequence Patterns

Concept Description Example
Repeating Pattern A sequence where a specific block of elements (letters, numbers, symbols) repeats one or more times. ABCABCABC (ABC repeats)
Alternating Pattern A sequence where elements alternate in a specific order. ABABAB (A and B alternate)
Increasing/Decreasing Pattern A sequence where the change between elements follows a rule (e.g., add 2 each time). More common in number series. A, C, E, G (Letters skip one)

Additional Information: Solving Letter Series Questions

Letter series questions often require identifying the rule or pattern that governs the sequence. Common patterns include:

  • Repeating blocks of letters.
  • Letters skipping a fixed number of letters in the alphabet (e.g., A, C, E, G skips one letter each time).
  • Letters moving forward or backward in the alphabet by a varying number.
  • Combinations of letters and numbers.
  • Patterns based on letter positions in the alphabet (A=1, B=2, etc.).

To solve these problems, it's helpful to:

  • Write down the sequence clearly, marking the blanks.
  • Look for repeating segments, especially if the sequence is long.
  • Consider the position of letters in the alphabet if repeating patterns aren't obvious.
  • Test the given options by filling the blanks and checking if a logical pattern emerges.
Was this answer helpful?

Similar Questions

  1. Which one of the following statements best reflects the most logical and rational message conveyed by the author of the passage?

  2. With reference to the above passage, the following assumptions have been made:
    I. There is no need for the State to be involved in any manner in the handloom sector.
    II. Handloom products are no longer appealing and attractive in the rapidly changing modern world.
    Which of the above assumptions is/are valid?

  3. Which one of the following statements best reflects the central idea conveyed by the passage?

  4. Which one of the following statements best reflects the central idea conveyed by the passage?

  5. With reference to the above passage, the following assumptions have been made:
    I. Global climate change can result in the migration of several plant diseases to new areas.
    II. Scientific understanding of the wild relatives of our present crops would enable us to strengthen food security.
    Which of the above assumptions is/are valid?

  6. Which one of the following statements best reflects the critical message conveyed by the author of the passage?

  7. With reference to the above passage, the following assumptions have been made:
    I. Path-dependent green investments will eventually most likely benefit growth as well as public finances in a country like India.
    II. If other green technologies follow the same pattern as that of solar energy, there will most likely be an easy green transition.
    Which of the above assumptions is/are valid?

  8. A natural number N is such that it can be expressed as N = p + q + r, where p, q and r are distinct factors of N. How many numbers below 50 have this property?

  9. Team X scored a total of N runs in 20 overs. Team Y tied the score in 10% less overs. Had Team Y’s average run rate (runs per over) been 50% higher, the scores would have been tied in 12 overs. How many runs were scored by Team X?

  10. A 4-digit number N is such that when divided by 3, 5, 6, 9 leaves a remainder 1, 3, 4, 7 respectively. What is the smallest value of N?


Important Questions from Miscellaneous Topics

  1. In communication the word 'Haptics' signifies :
  2. Which of the following statements best defines the scope of semiotics?
  3. The compound interest on Rs. 75,000 for three years, at successive interest rates of 4%, 6% and 9% for each year respectively is:

  4. The value of x in the following figures is :

  5. When a child reaches adolescence, there is apt to be a conflict between the parents and the child, since
    the latter considers himself to be by now quite capable of managing his own affairs, while the former
    are filled with parental solicitude, which is often a disguise for love of power. Parents consider, usually,
    that the various moral problems which arise in adolescence are peculiarly their province. The options
    they express, however, are so dogmatic that the young seldom confide in them, and usually go their
    own way in secret.

Need Expert Advice?
Upcoming Exams
UPSC IFoS
November 22, 2026
UPSC SO Steno
December 12, 2026
Test Series
IAS img
UPSC
UPSC CSE (IAS) 2027 Prelims Mock Test Series
662 Tests 3 Tests Free
1707 Attempts
4.8(203)
English, Hindi
More Questions from IAS

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App