Difficulty: Easy
Correct Answer: 25 18
Explanation:
Introduction / Context:
This series interleaves two independent arithmetic progressions, one increasing and one decreasing. Such paired sequences are routine in aptitude exams.
Given Data / Assumptions:
Concept / Approach:
Split by position: Odd-index terms and even-index terms. Compute each pattern separately.
Step-by-Step Solution:
Odd positions (1st, 3rd, 5th, 7th): 10, 12, 14, 16 → increment +2 each time; next odd (9th) will be 18.Even positions (2nd, 4th, 6th): 34, 31, 28 → decrement −3; next even (8th) will be 25.Hence the next two numbers (8th then 9th) are 25 and 18.
Verification / Alternative check:
List the two progressions: Even: 34, 31, 28, 25; Odd: 10, 12, 14, 16, 18. Interleaving confirms the answer 25 18.
Why Other Options Are Wrong:
Common Pitfalls:
Ignoring position-based splitting; without it the numbers look erratic.
Final Answer:
25 18
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