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John Adair's 100 Greatest Ideas for Smart Decision Making by John Adair

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Idea 67: Dots and matchsticks

Please solve the following two problems.

Problem 1: The Nine Dots

Take a piece of paper larger than this page and put on it a pattern of nine dots, like this:

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Now, without taking your pen or pencil off the paper, connect up the dots by four straight consecutive lines. You should be able to complete this task within three minutes.

Problem 2: The Six Matchsticks

Place six matchsticks – preferably of the wooden variety – on a flat surface. Now arrange the matchsticks in a pattern of four equilateral (i.e. equal-sided) triangles. You may not break the matchsticks – that is the only rule.

Again, you should be able to ...

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