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2015 Math Kangaroo

Problem 5

Problem 5 · 2015 Math Kangaroo Easy
Spatial & Visual Reasoning spatial-reasoning
Figure for Math Kangaroo 2015 Problem 5
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Answer: B
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Hint 1 of 2
Mark everything that is far enough from the hedge, then keep only the part close enough to the tree.
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Hint 2 of 2
The answer is the overlap: outside the 5 m strip along the hedge and inside the 5 m circle around the tree.
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Approach: intersect the two distance conditions
  1. “At least 5 m from the hedge” removes a 5 m strip next to the hedge.
  2. “No more than 5 m from the tree” keeps a disc of radius 5 m around the tree.
  3. The valid spot is where both hold: the part of the tree's disc lying beyond the hedge strip.
  4. The picture matching this overlap is (B).
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