C fires at city B and D fires at city A, but their rockets collide in mid-air and fall into the ground at F. Then C fires a laser bouncing off the ground at F at the same angle as incidence. Will the laser beam hit combatant D?
Author: Marshall W. Buck
Two circles, a rectangle and two line segments. Prove that the red points are collinear.
Two squares sharing a vertex and a line segment. What’s the yellow area?
An equilateral triangle with two perpendiculars to a point that is at the same height as the triangle centre. What is red : yellow?
Behold a 13-14-15 triangle. The 15-long side is dissected into 5 equal parts and the 14-long side is dissected into 7 equal parts. What is the difference between the red and green areas?
Author: Marshall W. Buck.
Two rectangles share two vertices. What’s the green fraction?
Three squares and a circle. The red point is a common intersection of two square sides and the circle. What is blue : green?
Two blue squares and two red right triangles. What are the proportions of the triangle sides?
Author: Matthew Arcus.
Two squares share a vertex. What’s blue : green : orange?
Two points are on opposite sides of a channel. A skew bridge, which has a fixed direction (for instance North East), can be placed anywhere along the channel. Where to place it such that the path from A to B over the bridge is the shortest?