Analyzing the Letter Series Pattern

The question asks us to find the sequence of letters that completes the given letter series. We are provided with a series containing blanks and several options. We need to test the options to find a logical pattern in the completed series.

The given series is:

C ___ ___ UP ____ EX ____ PC ____ XU ___ ___ E ___ UP

Let's note the positions and lengths of the blanks:

• Blank 1: 2 letters
• Blank 2: 1 letter
• Blank 3: 1 letter
• Blank 4: 1 letter
• Blank 5: 2 letters
• Blank 6: 1 letter

The total number of blank spaces is $2 + 1 + 1 + 1 + 2 + 1 = 8$. Each option provides a sequence of 8 letters to fill these blanks in order.

Testing the Options to Complete the Series

Let's take the correct sequence of letters from the options and place them into the blanks:

The sequence of letters to be inserted is EXCUEPCX.

Inserting these letters into the blanks sequentially from left to right:

• The first 2 letters (EX) go into the first blank.
• The 3rd letter (C) goes into the second blank.
• The 4th letter (U) goes into the third blank.
• The 5th letter (E) goes into the fourth blank.
• The 6th and 7th letters (PC) go into the fifth blank.
• The 8th letter (X) goes into the sixth blank.

Let's see the completed series by inserting EXCUEPCX:

Original: C _ _ UP _ EX _ PC _ XU _ _ E _ UP

Inserted: E X C U E P C X

Completed Series: C E X UP C EX U PC E XU P C E X UP

Identifying the Letter Series Pattern

Let's look at the completed series: C E X U P C E X U P C E X U P C X E X U P

Observing this sequence, we can see a repeating block of letters:

• The first block is CEXUP.
• The second block is CEXUP.
• The third block is CEXUP.
• The fourth block is C X E X U P.

The pattern appears to be the sequence 'CEXUP' repeating three times, followed by a slightly varied sequence 'CXEXUP'.

Let's map the letters from the correct option (EXCUEPCX) to how they complete this repeating pattern:

Let's reconsider the completed series with the correct fill: C E X U P C E X U P C E X U P C X E X U P

The repeating block is indeed 'CEXUP'. Let's highlight the letters contributed by the fill 'EXCUEPCX' within this completed series:

C E X UP C EX U PC E XU P C E X UP

Mapping these back to the blanks:

• Blank 1 (pos 2-3): EX
• Blank 2 (pos 6): C
• Blank 3 (pos 9): U
• Blank 4 (pos 12): E
• Blank 5 (pos 15-16): PC
• Blank 6 (pos 19): X

This matches the sequence EXCUEPCX.

The pattern is based on the repeating block CEXUP. The series is formed by repeating this block three times, followed by a modified block.

Block 1: CEXUP

Block 2: CEXUP

Block 3: CEXUP

Block 4: CXEXUP

The letters from the correct option (EXCUEPCX) perfectly fit into the blanks to create this repeating pattern (with the final variation).

Conclusion on the Letter Series Completion

By inserting the letters EXCUEPCX into the blanks of the series C ___ ___ UP ____ EX ____ PC ____ XU ___ ___ E ___ UP, we obtain the sequence CEXUPCEXUPCEXUPCXEXUP. This sequence exhibits a clear repeating pattern of 'CEXUP', making EXCUEPCX the correct option to complete the letter series.

Revision Table: Key Concepts in Letter Series

Additional Information on Series Completion

Letter series completion questions are common in aptitude tests and competitive exams. They assess logical reasoning and pattern identification skills. To solve these problems effectively, consider the following approaches:

• Look at the difference in alphabetical position between consecutive letters (e.g., A to C is +2).
• Check for repeating blocks of letters.
• Look for patterns based on vowels and consonants.
• Consider patterns in the position of letters within words or groups if spaces are present.
• Sometimes, the pattern might involve two interleaved series.
• For complex series, write down the alphabetical position of each letter and look for numerical patterns.

Practice with various types of letter series problems helps in quickly identifying the underlying pattern.