Difficulty: Easy
Correct Answer: 11 8
Explanation:
Introduction / Context:This arithmetic progression decreases steadily by a constant amount. Accuracy in repeated subtraction is all that is needed.
Given Data / Assumptions:
Concept / Approach:Extend by subtracting 3 sequentially from the last term provided.
Step-by-Step Solution:
After 14, next is 14 − 3 = 11.Then 11 − 3 = 8.Verification / Alternative check:Rebuild tail: 20, 17, 14, 11, 8 maintains −3 each time.
Why Other Options Are Wrong:
Common Pitfalls:Miscalculating one of the subtractions when working quickly.
Final Answer:11 8
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