Question

11, 13, 17, 19, 23, 25, ?

• A. 29
• B. 27
• C. 31
• D. 37

Hint:

Look for alternating patterns such as primes + arithmetic increments when differences are irregular.

Answer 1

The Correct Option is A

To solve this sequence problem, we need to identify the pattern in the given numbers. Let's list the numbers:

• 11 
• 13
• 17
• 19
• 23
• 25

Upon inspection, it seems that the sequence alternates between prime numbers and non-prime numbers:

• 11 - Prime
• 13 - Prime
• 17 - Prime
• 19 - Prime
• 23 - Prime
• 25 - Non-prime (as 25 = 5 × 5)

In this sequence, every alternate number is a prime number, and the non-prime numbers are placed at specific intervals. Let's observe the pattern:

1. The prime numbers are positioned at odd places in the sequence: 1st, 3rd, 5th...
2. Non-prime numbers are positioned at even places in the sequence: 6th, 8th...

According to the pattern, the numbers at the 1st, 3rd, 5th positions are prime numbers, and the given sequence has its next expected number as a non-prime number, but after 25, the next sequence should resume to a prime number:

After the number 23 (5th prime position) and 25 (6th position as non-prime), the next in sequence is a prime:

• The next prime after 23 is 29.

Therefore, the answer to the sequence is:

29

This fits the rule of alternating between selecting prime and non-prime (for illustration only; actual position remains prime).

Hence, the answer is 29.