What number should replace the question mark in the following sequence?
12, 6, 6, 9, 18, ?

Correct option is D

Sol. Let’s analyze the pattern step by step: 12 → 6 (÷2) 6 → 6 (×1) 6 → 9 (×1.5) 9 → 18 (×2) 18 → ? (×2.5) So, 18 × 2.5 = 45
Explanation of each option:
· (a) 36 – Incorrect. Doesn’t match the multiplication pattern of ×2.5.
· (b) 30 – Incorrect. Also fails the sequence logic.
· (c) 48 – Incorrect. 18 × 2.5 is 45, not 48.
· (d) 45 – Correct. The pattern follows progressive multiplication: ×1, ×1.5, ×2, ×2.5 → 45.