# Tic Tac Toe Grid

Pro Problems > Math > Statisics and Probabilities > Counting Principles## Tic Tac Toe Grid

Begin with a 3 x 3 grid, like the one used to play Tic Tac Toe. You have a blue square, a green square, and a red square, that you can place within the grid, according to the following rules:

- The green square must be touching the blue square on a side.
- The red square must be touching the green square on either a side or a vertex.
- No square can be placed on top of another square.

For example, the following arrangement is valid, because the green is horizontally connected to the blue square, and the red square is diagonally connected to the green square.

In how many different ways could the three squares be placed on the grid?

## Solution

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