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Folding Squares
Age 14 to 16
Challenge Level 
Start with a square...
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Fold to create a diagonal running from bottom left to top right. |
Find the midpoint of the base by folding. |
Fold the paper again, joining the top left corner to the midpoint of the base. |
What fractions of the diagonal do you think your new fold has created? |
Measure the two sections of the diagonal and compare their lengths.
What do you notice?
Is this what you expected?
Is this what you expected?
Can you produce a convincing mathematical argument or proof that justifies what you have found?
You might like to try A Parallelogram Trisection and Folding Fractions next.
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