Difficulty: Medium
Correct Answer: 14
Explanation:
Introduction / Context:
This sequence alternates between adding and subtracting shrinking amounts. The absolute size of the step decreases in a regular fashion across the series.
Given Data / Assumptions:
Concept / Approach:
Compute consecutive differences and look at absolute values: 8→43 = +35; 43→11 = −32; 11→41 = +30. The magnitudes 35, 32, 30 suggest a pattern decreasing by 3, then 2, repeating over positive and negative steps.
Step-by-Step Solution:
Following +35, −32, +30, the next should be a negative step with magnitude 27 (30 − 3).41 − 27 = 14, so the missing term is 14.Next difference should be +25 (27 − 2), and 14 + 25 = 39, which matches the next given term.
Verification / Alternative check:
Continuing the rule would give the next step −22 (25 − 3): 39 − 22 = 17, which also matches the following term.
Why Other Options Are Wrong:
Common Pitfalls:
Checking only one side of the blank. Always ensure the candidate fits both the prior and the subsequent term under a single consistent rule.
Final Answer:
14
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