Difficulty: Medium
Correct Answer: 57
Explanation:
Introduction / Context:Targeted-divisor checks (like 19) often produce a unique outlier in a small set.
Given Data / Assumptions:
Concept / Approach:Compare with nearby multiples: 19, 38, 57, 76, 95, 114, 133, …
Step-by-Step Solution:
57 = 19 * 3 → multiple of 19.39 = 3 * 13 → not a multiple of 19.69 = 3 * 23 → not a multiple of 19.117 = 9 * 13 → not a multiple of 19 (note: 19 * 6 = 114).Verification / Alternative check:Dividing each by 19: only 57/19 = 3 is an integer.
Why Other Options Are Wrong:They are not multiples of 19; 117 is close (114 is 19 * 6) but not equal.
Common Pitfalls:Choosing numbers near a multiple of 19 (e.g., 117) instead of exact multiples.
Final Answer:57 is the only multiple of 19 and hence the odd number.
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