Problems(2)
equilateral, can be covered by 5 equilaterals (2017 HOMC Junior Q9)
Source:
8/3/2019
Prove that the equilateral triangle of area can be covered by five arbitrary equilateral triangles having the total area .
geometryEquilateral
2018 pieces by cutting 2017 times a square, numbers 0,1,2 (HOMC 2017 S Q9)
Source:
9/8/2019
Cut off a square carton by a straight line into two pieces, then cut one of two pieces into two small pieces by a straight line, ect. By cutting times we obtain pieces. We write number in every triangle, number 1 in every quadrilateral, and in the polygons. Is the sum of all inserted numbers always greater than ?
combinatoricscombinatorial geometry