Number series – decreasing by multiples of 9 (−81, −72, −63, −54, −45): 435, 354, 282, 219, 165, ?

Introduction / Context:This is a steady decrement where each subtraction is 9 less than the previous subtraction. Such “step-down by a fixed amount” patterns are quick once spotted.

Given Data / Assumptions:

• 435→354=−81, 354→282=−72, 282→219=−63, 219→165=−54.

Concept / Approach:Subtractions are 81, 72, 63, 54 (each reduces by 9). The next subtraction is 45.

Step-by-Step Solution:

Verification / Alternative check:Adding 45 back to 120 returns 165, preserving the −9 ladder.

Why Other Options Are Wrong:

Common Pitfalls:Assuming constant subtraction (not the case); here the subtraction itself decreases linearly.

Final Answer:120