Maths Olympiad Prep

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, 2020

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

There are some squares and triangles on the table. Some of them are blue and the rest are red. Some of these shapes are large and the rest are small. We know that
1. If the shape is large, it's a square;
2. If the shape is blue, it's a triangle.
Which of the statements A–E must be true?

(A) All red figures are squares. (B) All squares are large. (C) All small figures are blue. (D) All triangles are blue. (E) All blue figures are small.

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