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

Difficulty: Easy

Correct Answer: 120

Explanation:


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:

Next term = 165 − 45 = 120.


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



Why Other Options Are Wrong:

103/112/130 imply −62/−53/−35, which do not fit the −9 cadence.


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



Final Answer:
120

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