Oopsie. Chelle didn't know that part about Babylonia, so she took her quill and some parchment and began to scribble it down. She would have to do a little more research from now on before coming for Arithmancy. Yup.

Why was 9 left out?

This was one question she was confident about. A few days ago, she had been wondering the same thing, and she had gone looking for the answer by herself. This was an easy one. "Professor, the number 9 was left out of the Chaldean Number System because the Chaldeans felt that the number 9 was holy, sacred and thus to be held apart from the rest," she replied.