K12 Math Puzzles
Can you construct nine triangles by drawing three straight lines through a capital
3 sticks of uncooked spaghetti
or 3 toothpicks
or whatever other manipulative is handy to simulate the lines
- Draw a large M on your paper.
- Use the 3 sticks and try various ways to place them across the M.
Questions to ask yourself as you work:
- Are any triangles formed if you place one of the sticks vertically?
- Are any triangles formed if you place one of the sticks horizontally?
- What is the maximum number of triangles you can make by placing just one stick?
- When you have placed one stick, look at the triangles that you have made. How
many more triangles do you still need to make?
- You have 2 sticks left. Can you place them so that you will cross existing triangles
and thereby double the number of triangles?
(Don't look 'til you're ready to give up!)
* Thanks to Robert Arnett, who sent this question to the Forum.
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