Analyzing the Letter Series Pattern

The given series is L, S, M, P, N, M, O, J, P, ?. We need to find the letter that replaces the question mark based on the pattern in the series.

Let's look at the alphabetical positions of the letters:

• L is the 12th letter.
• S is the 19th letter.
• M is the 13th letter.
• P is the 16th letter.
• N is the 14th letter.
• M is the 13th letter.
• O is the 15th letter.
• J is the 10th letter.
• P is the 16th letter.

The series of alphabetical positions is: 12, 19, 13, 16, 14, 13, 15, 10, 16, ?

Identifying Interleaved Series

Looking closely at the sequence of letters, it appears there might be two different patterns interleaved within the main series.

Let's separate the letters at odd positions (1st, 3rd, 5th, 7th, 9th, ...):

L, M, N, O, P

Let's look at their positions:

12, 13, 14, 15, 16

This is a simple arithmetic progression where each term is increasing by 1. The pattern is $\text{Letter} + 1$.

Now, let's look at the letters at even positions (2nd, 4th, 6th, 8th, 10th, ...):

S, P, M, J, ?

Let's look at their positions:

19, 16, 13, 10, ?

This is also an arithmetic progression, but in decreasing order. Each term is decreasing by 3. The pattern is $\text{Letter} - 3$.

Determining the Next Letter

The question mark is at the 10th position, which is an even position. Therefore, the pattern from the second series (even positions) applies here.

The last known letter in the second series is J, which is at the 8th position in the original series and has an alphabetical position of 10.

Applying the pattern $\text{Letter} - 3$:

The position of the next letter = Position of J - 3

Position of the next letter = $10 - 3 = 7$

The 7th letter in the alphabet is G.

So, the letter that replaces the question mark is G.

Summary of Patterns

Conclusion

By identifying the two interleaved series, we found that the second series follows a pattern of subtracting 3 from the alphabetical position of the previous letter in that sub-series. Applying this pattern to J (position 10) gives us a position of 7, which corresponds to the letter G.

Revision Table: Letter Series Concepts

Additional Information: Solving Letter Series

Solving letter series questions requires careful observation and trying out different potential patterns. Here are some common strategies:

• Convert to Numbers: Assign numerical values (A=1, B=2, ...) to the letters. This often makes mathematical patterns easier to spot.
• Look for Arithmetic/Geometric Patterns: Check if the numerical values follow an arithmetic (add/subtract constant) or geometric (multiply/divide constant) progression.
• Check for Interleaved Patterns: Separate the series into sub-series (e.g., odd positions vs. even positions) to see if simpler patterns emerge within them.
• Look for Reverse Alphabetical Order: Sometimes the pattern involves moving backward through the alphabet.
• Consider Vowels/Consonants: The pattern might relate to the sequence of vowels or consonants.
• Check for Positional Patterns: The pattern might relate to the position of the letter in the English alphabet (e.g., skipping a fixed number of letters).

Practice with various types of series helps in quickly recognizing common patterns.