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Consider the following card game:

A set of nine cards numbered 1 to 9. Two players in turns pick up a card. The winner is the player who first have three of his cards add up to 15.

For instance, in the fourth turn Player A gets 1,2,3,9 and Player B gets 4,5,6,7, then Player B wins the game as 4+5+6=15.

Better have a try first before continue to read.

*Three classes of 1-9 tiles in Mahjong. [Source: Wikimedia Commons]*

If we talk about an IQ game involving 1 to 9, which game comes to your mind?

Let me guess: the magic square! Arrange the nine cards in a magic square.

8 | 1 | 6 |

3 | 5 | 7 |

4 | 9 | 2 |

Now plays the card game again.

Have you noticed that you are just playing Tic-Tac-Toe?

It is a game that you may already dismiss as too childish long time ago.

Old thing can be new again if it is given a completely different look.