Math Monday: Slice a Bagel into 13 Pieces with Three Cuts (Our 100th Column!)
Celebrate the one hundredth “Math Monday”> column with a return to yet another mathematical way to slice bagels.
Math Monday
Math Monday: Make a Ball of Cards
Two years ago, we looked at some constructions made from playing cards that are slotted and slid together. Here is a new one, by Zach Abel.
Math Monday: What to Make from Binder Clips?
We push the boundaries of binder clip assembly and offer a number of novel constructions.
Math Monday: Four Paper Triangles
What could sound easier than to make a regular construction from four paper equilateral triangles? One possible construction is the regular tetrahedron, which is pretty easy. Here is a different construction from four equilateral triangles. Each triangle is linked with the other three, like two links of a chain.
Math Monday: An Octahedron in a Balloon
You may know how to make a ship in a bottle, but how would you make this octahedron in a balloon? The twelve edges of the octahedron are made of strips of blue balloon rubber, glued to the inside of the clear balloon at the six vertices. Think of how you might make this before reading my solution below.
Math Monday: Light Stick Construction
Inexpensive light sticks can be held together with rubber bands to make glowing geometric structures. Here’s a construction based on the truncated dodecahedron, with a tetrahedron over each triangle. Assembling it is a fun group activity.
Math Monday: String Hyperboloid
A string hyperboloid can be made by running strings between two circles and rotating one relative to the other. Here’s one large enough to stand inside of—it is fourteen feet high—between four-foot diameter circles.
