What comes next: 3, 12, 7, 16, 11, 20, 15, ?

Question

What comes next: 3, 12, 7, 16, 11, 20, 15, ?

1. A. 16
2. B. 24 (Correct answer)
3. C. 14
4. D. 18

Correct Answer

Option B — 24

Detailed Solution & Explanation

The correct answer is 24.

Key Points

• This is two interleaved sequences.
• The odd positions 3, 7, 11, 15 rise by +4; the even positions 12, 16, 20, ? also rise by +4. The next term sits in the even sequence, so 20 + 4 = 24.
• Alternating series look irregular as a single list — split them into the odd-indexed and even-indexed subsequences and each becomes a simple arithmetic progression.