Decreasing number series analysis: 325, 259, 204, 160, 127, 105, ? — determine the next value by inspecting the changing subtractions between adjacent terms.

Difficulty: Easy

Correct Answer: 94

Explanation:


Introduction / Context:
This decreasing series tests your ability to spot a clean pattern in successive subtractions. Many such sequences reduce by steadily shrinking gaps, often by a fixed amount each step.



Given Data / Assumptions:

  • Sequence: 325, 259, 204, 160, 127, 105, ?
  • We expect a consistent rule in the differences.


Concept / Approach:
Compute the differences term-by-term and observe how the subtraction amount changes. If the “step-down” itself follows a simple pattern, extend that to predict the next reduction and, thus, the next term.



Step-by-Step Solution:

Differences: 325 − 259 = 66; 259 − 204 = 55; 204 − 160 = 44; 160 − 127 = 33; 127 − 105 = 22.The subtractions form: 66, 55, 44, 33, 22 — a pattern decreasing by 11 each time.Next subtraction = 22 − 11 = 11.Next term = 105 − 11 = 94.


Verification / Alternative check:
Following the “reduce by 11” rule backward and forward keeps the pattern consistent, confirming 94.



Why Other Options Are Wrong:

  • 96, 98, 100 would correspond to subtractions of 9, 7, or 5 from 105, which break the steady minus-11 pattern.


Common Pitfalls:
Trying to apply ratios or alternating rules before checking a straightforward arithmetic progression in the differences. Always test the simplest hypothesis first.



Final Answer:
94


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