This hint page will be built up as people ask for hints.

Rebecca Rapoport and Dean Chung

**Folks are discussing and posting solutions daily on Twitter**

Hint: For some of the problems, we figure you’ll look up a term mentioned in the problem and learn something new. For example, for January 1, you could google "prime-counting function" and go to wikipedia which will help you solve the problem.

Hint: The "..." means "and so on" in math. The problem contains continued fractions with alternating 8 and 9’s. You can learn more about continued fractions here

Hint: There is only one possible digit A can be. Otherwise the result of the multiplication would have 7 digits instead of 6.

There was an error in the image. If you ignore the missing angle completely, the problem is solvable (and the answer is as expected).

The problem is correct but the diagram could be easier to read. (The problem of the tiny space rears its head again.) Here's a blown up diagram that might make it clearer.

You can assume a, b, and c are integers > 0.

The image published in the calendar wasn't quite right. Here's the correct image.