Twelve matchsticks: focus or funnel
One of my favourite puzzles is the Twelve matchsticks puzzle. It goes like this:
| Twelve matchsticks can be laid on the table to produce a variety of shapes. If the length of a matchstick is 1 unit, then the area of each shape can be found in square units. For example, these shapes have areas 6, 9 and 5 square units. |
| Arrange twelve matchsticks into a single closed shape with area exactly 4 square units. |
I will tell you soon why this is one of my favourite puzzles, but first I want to tell you where I first learned this puzzle.
Once upon a time, about ten years ago, I met a lecturer at my university who was designing a course called Puzzle-Based Learning. It was an interesting c