Problem 11 · 2009 Math Kangaroo
Medium
Spatial & Visual Reasoning
path-tracing
Which of the figures shown is made using more than one piece of string?
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Answer: C — I, III and V
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Hint 1 of 2
Trace each diagram: a single loop returns to its start without lifting.
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Hint 2 of 2
If you cannot travel the whole figure as one continuous loop, it needs more than one piece.
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Approach: trace each loop
- Follow each knot diagram as a path: a single string forms one closed loop.
- Figures II and IV can each be traced as one loop, so they use one piece of string.
- Figures I, III and V cannot be drawn as a single loop, so each uses more than one piece.
- The answer is I, III and V.
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