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Problem 348

Geometry Difficulty 2.0 Find the answer UKMT Pink Kangaroo · United Kingdom · 2015

Martha draws some pentagons, and counts the number of right-angles in each of her pentagons. No two of her pentagons have the same number of right-angles. Which of the following is the complete list of possible numbers of right-angles that could occur in Martha's pentagons?

(A) $1, 2, 3$ (B) $0, 1, 2, 3, 4$ (C) $0, 1, 2, 3$ (D) $0, 1, 2$ (E) $1, 2$

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