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Have You Got It?

Can you explain the strategy for winning this game with any target?

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Traffic Lights

The game uses a 3x3 square board. 2 players take turns to play, either placing a red on an empty square, or changing a red to orange, or orange to green. The player who forms 3 of 1 colour in a line wins.

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Yih or Luk Tsut K'i or Three Men's Morris

Some puzzles requiring no knowledge of knot theory, just a careful inspection of the patterns. A glimpse of the classification of knots and a little about prime knots, crossing numbers and knot arithmetic.


Stage: 2 and 3 Challenge Level: Challenge Level:1

To play the game, take cards alternately. You win if you get all the occurrences of the same letter. (e.g. AN, ON and LINE contain all occurrences of the letter N)

Can you devise a strategy so that you never lose?

Can you explain your strategy?

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You can print these cards out to play if you like.


Look at all of these games. What do you notice about the strategies they employ?

We suggest tackling them in the order given.

Printable NRICH Roadshow resource. 

Click here for a poster of this problem.