Problem 3 · 2024 Math Kangaroo
Easy
Spatial & Visual Reasoning
path-tracing
Which figure shown below cannot be formed from the rope shown on the right without cutting it?
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Answer: B
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Hint 1 of 2
A single uncut loop of rope is one continuous strand with no loose ends and no extra pieces.
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Hint 2 of 2
Trace each picture as one closed curve; the impossible one would need the rope cut and rejoined.
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Approach: check which tangle is a single closed loop of the same rope
- The starting rope is one closed loop (a figure-eight), so any reachable shape is still one unbroken loop.
- Four of the pictures can be made by twisting and crossing that single loop.
- One picture cannot be traced as one continuous loop without cutting.
- That impossible figure is B.
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