3 out of 3
How can you make an angle of 60 degrees by folding a sheet of paper twice?
3 out of 3
A 3×3×3 cube may be reduced to unit cubes in six saw cuts. If after every cut you can rearrange the pieces before cutting straight through, can you do it in fewer?
3 out of 3
Show that among the interior angles of a convex polygon there cannot be more than three acute angles.
3 out of 3
Anne completes a circuit around a circular track in 40 seconds. Brenda runs in the opposite direction and meets Anne every 15 seconds. How long does it take Brenda to run around the track?
3 out of 3
Weekly Problem 52 - 2012
An irregular hexagon can be made by cutting the corners off an equilateral triangle. How can an identical hexagon be made by cutting the corners off a different equilateral triangle?
3 out of 3
Jack and Jill run at different speeds in opposite directions around the maypole. How many times do they pass in the first minute?
3 out of 3
Take a line segment of length 1. Remove the middle third. Remove the middle thirds of what you have left. Repeat infinitely many times, and you have the Cantor Set. Can you picture it?
3 out of 3
Weekly Problem 37 - 2010
An ant is crawling around the edges of a cube. From the description of his path, can you predict when he will return to his starting point?
