Stage: 1 Challenge Level:
Can you imagine the square on the back? Where will its $1$ be?
Where will its $10$ be?
So what will be on the back of the $20$ in the $100$ square in the
picture? The $30$? Does this help with the $100$?
You could print off the $100$ square, or draw your own, and write
just, for example, $1-10$ on the back of it to get you started. Can
you see where $11-20$ would be? Perhaps this helps to predict the