K12 Math Puzzles
Join the Dots
Can you connect 9 dots laid out 3x3 using 4 straight lines, without lifting your
pencil from the paper?
4 sticks of uncooked spaghetti and 9 pennies
or 4 toothpicks and 9 Cheerios or other flat breakfast cereal
or whatever other manipulative is handy to simulate the lines and dots
- Place 9 "dots" on your desk or table.
- Using the 4 sticks experiment with connecting the dots using 4 straight lines.
(Or just use pencil and paper.)
Questions to ask yourself as you work:
- Can you do the puzzle if the lines do not cross each other?
- Must your lines stay within the grid of dots?
- What if you extend a line past the edges of the arrangement of dots?
(Don't look 'til you're ready to give up!)
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