Problem:
An equilateral triangle of side length is completely filled in by non-overlapping equilateral triangles of side length . How many small triangles are required?
Answer Choices:
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B.
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Solution:
The side length of the large triangle is times the side length of each small triangle, so the area of the large triangle is times the area of each small triangle.
The problems on this page are the property of the MAA's American Mathematics Competitions