Hitting the Target Puzzle

Here's a quick puzzle. In the attached image, a circle is inscribed in a square which is inscribed in another circle.

Of the outside yellow ring, or the inside magenta circle, which has the bigger area, and why?

Playing with Blocks

Here's a fun puzzle to ponder.

A certain number of faces of a large wooden cube are stained. Then the block is divided into equal-sized smaller cubes. Counting we find that there are exactly 45 smaller cubes that are unstained. How many faces of the big cube were originally stained?

Feel free to add a comment with your answer, along with how you solved it.

Create a foldable 3-D dodecahedron calendar

I discovered a fascinating site a few years back and completely forgot about it. You've probably seen a 3-D calendar with each month on one of the faces of a dodecahedron. But have you ever wanted to print and construct your own? Ole Arntzen of Norway created a webpage that lets you pick a year, a language and a few other options and then it creates a printable template for a 12-sided calendar.

You can generate a ready-to-print PDF file, or an editable PostScript file. With a little editing of the PS file, you can add holidays, birthdays, school breaks, anniversaries, etc. Take a look!

The Disguised Triangles Revisited...

A couple months back I posted this picture and asked people to count how many different triangles are in the hexagonal pattern to the right. It is now time to reveal the answer. Click the picture for the solution.

The Disguised Triangles

How many different triangles can you find in the hexagonal pattern to the right? I believe I correctly counted them all and will post my answer sometime in the future...