Understanding the Question Sequence Pattern

The question asks us to carefully examine the given sequence of symbols, letters, and numbers: $M@A#N2B4O&3C5P+D2.

We need to find the number of letters within this sequence that meet two specific conditions simultaneously:

• The letter must be immediately preceded by a symbol.
• The letter must be immediately followed by a number.

So, we are looking for instances of the pattern: Symbol - Letter - Number.

Analyzing the Elements in the Sequence

Let's list out the elements of the sequence and identify what each one is:

Scanning for the Symbol-Letter-Number Pattern

Now, let's go through the sequence from left to right and check each letter to see if it fits the required pattern (preceded by a symbol and followed by a number).

• Letter M: Preceded by '$' (Symbol), Followed by '@' (Symbol). Does not match the pattern.
• Letter A: Preceded by '@' (Symbol), Followed by '#' (Symbol). Does not match the pattern.
• Letter N: Preceded by '#' (Symbol), Followed by '2' (Number). Matches the pattern! (#N2)
• Letter B: Preceded by '2' (Number), Followed by '4' (Number). Does not match the pattern (preceded by number, not symbol).
• Letter O: Preceded by '4' (Number), Followed by '&' (Symbol). Does not match the pattern (preceded by number).
• Letter C: Preceded by '3' (Number), Followed by '5' (Number). Does not match the pattern (preceded by number).
• Letter P: Preceded by '5' (Number), Followed by '+' (Symbol). Does not match the pattern (preceded by number).
• Letter D: Preceded by '+' (Symbol), Followed by '2' (Number). Matches the pattern! (+D2)

Counting the Instances of the Pattern

Based on our scan, the letters that are preceded by a symbol and followed by a number are N and D.

We found 2 instances where the pattern Symbol-Letter-Number occurs:

• #N2
• +D2

Therefore, the total number of such letters in the given sequence is 2.

Additional Information: Tips for Sequence Reasoning Questions

Sequence reasoning questions involve finding patterns or counting elements based on specific rules within a given sequence of characters. Here are some tips for tackling such questions:

• Understand the Rules: Carefully read the question to understand exactly what pattern or condition you are looking for. Identify the elements (symbols, letters, numbers) involved.
• Break Down the Sequence: If the sequence is long, it can be helpful to write it out and perhaps even label each character's type (symbol, letter, number).
• Scan Methodically: Go through the sequence one element at a time, from beginning to end. Don't skip around.
• Check Conditions Locally: For conditions based on preceding or following characters, always look at the elements immediately next to the character in question.
• Keep Track of Findings: Use a pen and paper, or a mental note, to mark or list the instances that meet the criteria.
• Double Check: After your initial scan, quickly go through the sequence again to ensure you haven't missed any instances or misapplied the rules.

Applying a systematic approach like this helps avoid errors and ensures you find all qualifying elements in the sequence.