Analyzing the Alphabet and Number Series Pattern

This question asks us to find the missing term in the given series: A7F, E15J, I23N, ?

To solve this, we need to identify the pattern for each component of the terms: the first letter, the number, and the second letter.

Step-by-Step Series Analysis

First Letter Analysis

Let's look at the sequence of the first letters:

• A (1st letter)
• E (5th letter)
• I (9th letter)
• ?

We can find the difference in position between consecutive letters:

• E is 4 positions after A ($5 - 1 = 4$)
• I is 4 positions after E ($9 - 5 = 4$)

The pattern for the first letter is adding 4 to the alphabetical position. So, the next letter should be 4 positions after I.

I is the 9th letter. The next letter's position will be $9 + 4 = 13$. The 13th letter of the alphabet is M.

So, the missing term starts with M.

Number Analysis

Now let's examine the sequence of numbers:

• 7
• 15
• 23
• ?

Let's find the difference between consecutive numbers:

• $15 - 7 = 8$
• $23 - 15 = 8$

The pattern for the number is adding 8 to the previous number. So, the next number should be 8 more than 23.

The next number will be $23 + 8 = 31$.

So, the missing term has 31 in the middle.

Second Letter Analysis

Finally, let's analyze the sequence of the second letters:

• F (6th letter)
• J (10th letter)
• N (14th letter)
• ?

We find the difference in position between consecutive letters:

• J is 4 positions after F ($10 - 6 = 4$)
• N is 4 positions after J ($14 - 10 = 4$)

The pattern for the second letter is also adding 4 to the alphabetical position. So, the next letter should be 4 positions after N.

N is the 14th letter. The next letter's position will be $14 + 4 = 18$. The 18th letter of the alphabet is R.

So, the missing term ends with R.

Combining the Components

Putting the components together:

• First letter: M
• Number: 31
• Second letter: R

The missing term in the series is M31R.

Conclusion

Based on the analysis of the patterns in the first letter, the number, and the second letter, the next term in the series A7F, E15J, I23N, ? is M31R.

Revision Table: Series Pattern

Understanding the individual patterns is key to solving such series questions.

• First Letter Pattern: Position increases by 4 each time (A+4=E, E+4=I, I+4=M).
• Number Pattern: Value increases by 8 each time (7+8=15, 15+8=23, 23+8=31).
• Second Letter Pattern: Position increases by 4 each time (F+4=J, J+4=N, N+4=R).

Additional Information: Solving Letter and Number Series

Series completion questions often involve patterns in alphabetical positions, numerical sequences, or a combination of both. Here are some tips for solving them:

• Break down each term into its components (letters, numbers, symbols).
• Analyze the pattern for each component separately.
• For letters, consider their position in the alphabet (A=1, B=2, ... Z=26). Look for patterns in the difference of positions.
• For numbers, look for arithmetic progressions (adding/subtracting a constant), geometric progressions (multiplying/dividing by a constant), squares, cubes, prime numbers, or alternating patterns.
• Combine the individual patterns to predict the next term.
• Always check your predicted term against the identified patterns for all components.

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