Understanding Letter Series Completion Questions

Letter series completion questions are a common type of logical reasoning problem. You are given a sequence of letters with some missing, and you need to find the pattern or rule governing the series to fill in the blanks correctly. The pattern might involve repeating blocks of letters, alphabetical progression, skipping letters, or a combination of rules.

The given series is: BR __ __ NB __ O __ NB

We need to choose the alternative from the given options that best completes this letter series. Let's examine the structure and the given letters carefully: B, R, N, B, O, N, B.

Analyzing the Given Letter Series BR __ __ NB __ O __ NB

The series has 7 given letters and 4 blanks, making a total length that will be determined by the option we choose (each option has 4 letters). Let's write down the series with placeholders for the blanks:

B R _ _ N B _ O _ N B

We have four blanks to fill. The options are:

1. WNWN
2. OWRW
3. OWOW
4. RORO

Testing the Options to Complete the Series

Let's try inserting each option into the blanks in the series and see if a clear pattern emerges.

Attempting Option 1: WNWN

Inserting WNWN into the blanks:

B R W N N B W O N N B

The resulting series is: B R W N N B W O N N B. It's difficult to see a simple repeating pattern in this sequence.

Attempting Option 2: OWRW

Inserting OWRW into the blanks:

B R O W N B R O W N B

The resulting series is: B R O W N B R O W N B. Let's look closely at this sequence. Can we identify a repeating block?

Let's try grouping letters:

BROWNB ROWNB

Yes, the sequence BROWNB seems to repeat. Let's write it out and compare it with the completed series:

B R O W N B

B R O W N B

Concatenating this block twice gives BROWNBROWNB.

Now, let's compare BROWNBROWNB with the series when Option 2 (OWRW) is filled:

B R O W N B R O W N B

B R _ _ N B _ O _ N B (Original series with blanks)

B R O W N B R O W N B (Series with Option 2)

The filled letters (O, W, R, W) perfectly complete the repeating pattern BROWNB.

Attempting Option 3: OWOW

Inserting OWOW into the blanks:

B R O W N B O O W N B

The resulting series is: B R O W N B O O W N B. This does not show a clear repeating pattern like BROWNB.

Attempting Option 4: RORO

Inserting RORO into the blanks:

B R R O N B R O O N B

The resulting series is: B R R O N B R O O N B. This also does not show a clear repeating pattern.

Identifying the Correct Pattern

Based on our analysis, inserting Option 2 (OWRW) reveals a clear and consistent repeating pattern: BROWNB.

The series is formed by repeating the block "BROWNB".

BROWNB BROWNB ...

Let's reconstruct the given series from this repeating block:

• The first two letters are BR, which matches the start of BROWNB.
• The next two letters are missing, these should be OW to complete BROWNB.
• The next two letters are NB, which matches the end of BROWNB and the start of the next block.
• The next letter is missing, this should be R to start the second BROWNB block.
• The next letter is O, which matches the second letter of the second BROWNB block.
• The next letter is missing, this should be W to continue the second BROWNB block.
• The final two given letters are NB, which matches the end of the second BROWNB block.

So, the missing letters are indeed O, W, R, W.

Conclusion

The correct alternative is Option 2, which provides the letters OWRW to complete the letter series according to the repeating pattern "BROWNB".

Revision Table: Key Concepts in Letter Series

Additional Information: Strategies for Solving Letter Series

When tackling letter series problems, consider the following strategies:

• Count the total number of letters (including blanks) to see if it's a multiple of a small number (like 2, 3, 4, 5, or 6). This can suggest the length of the repeating block. In our case, the completed series BROWNBROWNB has 11 letters. This length isn't a simple multiple. However, the pattern "BROWNB" is 6 letters long, and the series is effectively two repetitions followed by the first part of the third repetition if it were longer. The given series only extends to 11 letters, which accommodates one full "BROWNB" block and the first 5 letters of the next "BROWNB" block. Looking at the provided structure BR __ __ NB __ O __ NB (7 given + 4 blanks = 11 total), the pattern repeats across this 11-letter sequence.
• Look for sequences of consonants or vowels.
• Examine the gaps between letters if an alphabetical progression is suspected.
• Write down the position of each letter in the alphabet (A=1, B=2, etc.) to see if there's a numerical pattern.
• Try breaking the series into groups based on the options provided. Inserting an option can often reveal the hidden pattern.