Difficulty: Medium
Correct Answer: 634
Explanation:
Introduction / Context:
Many numeric sequences alternate between two fixed increments. Testing a simple +a, −b pattern often resolves such sets. Here, adding 23 and subtracting 17 alternately fits all but one term.
Given Data / Assumptions:
Concept / Approach:
Apply the alternating operations consecutively and compare the expected list with the given list. The mismatch pinpoints the odd term.
Step-by-Step Solution:
582 + 23 = 605 ✔605 − 17 = 588 ✔588 + 23 = 611 ✔611 − 17 = 594 (but the list shows 634) ✖Continuing the pattern from the correct 594: +23 ⇒ 617 ✔; −17 ⇒ 600 ✔
Verification / Alternative check:
Reconstructing the intended sequence yields: 582, 605, 588, 611, 594, 617, 600. Only 634 breaks the pattern, while all other terms align neatly when 594 is used in its place.
Why Other Options Are Wrong:
611/605/600 conform to the alternating +23/−17 rule; 634 does not and is therefore the odd entry.
Common Pitfalls:
Trying non-alternating progressions or varying step sizes, which complicates rather than clarifies the structure; overlooking that two neighbors can validate the intended steps.
Final Answer:
634
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