Minimum-count arrangement (ducks in line): Satisfy three positional descriptions simultaneously.
Requirement: “Two ducks in front of a duck”, “two ducks behind a duck”, and “a duck between two ducks”.
Find the smallest number of ducks that can satisfy all three statements at once.
Choose the correct minimum.
Difficulty: Easy
Correct Answer: 3
Explanation:
Visualize 3 ducks in a row D₁ — D₂ — D₃
Check conditions
Two in front of a duck: for D₃, ducks D₁ and D₂ are in front.
Two behind a duck: for D₁, ducks D₂ and D₃ are behind.
A duck between two ducks: D₂ is between D₁ and D₃.
Conclusion All three statements hold with just 3 ducks; fewer is impossible.
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