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Stage 2 - Problem 11

Problem: Coin Tic Tac Toe

Strand: Working Mathematically

Outcome: WMS2.2

Due: Wednesday 11th November

CoinsGrid
Until all six coins are played, Coin Tic-Tac-Toe is just like regular Tic-Tac-Toe. But once you start moving the coins around, it becomes a very different game. Strategy becomes very important.

RULES FOR COIN TIC-TAC-TOE--A GAME FOR TWO PEOPLE
1. One player (A) has the coins (heads up), the other (B) has the coins (tails up). A puts one coin in a square, then it's B's turn.
2. The first player to get 3 coins in a row is the winner.
3. If all 6 coins are down, but there is no winner (no one has 3 in a row), then the game changes.

After B puts down his last coin, A gets to move one of her coins, with these rules:

A coin can only be moved one square at a time.
A coin can only be moved into an empty square.
No diagonal moves allowed; only right, left, up, or down.
A coin can't jump over another coin.
A player has to move when it's his or her turn.
4. A and B keep moving their coins, in turn, until someone gets 3 in a row and wins the game.

HOW CAN I WIN?
Until all six coins are played, Coin Tic-Tac-Toe is just like regular Tic-Tac-Toe. But once you start moving the coins around, it becomes a very different game. Strategy becomes very important. Here are a few tips about moving the coins.

You can't move to just any empty square. You can only move a coin one square over. So try not to get yourself in a bind—having two coins in a row, but no way to move your third coin to join them.

If you surround the other player's coins with yours, he can't move the trapped coin. (And your opponent can do the same to you.)

Sometimes you can trap the other player's coins so that his only choice is to move out of the square that you want to move into.

Download Investigation Sheet. (Microsoft Word Document-56KB)


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