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Rectangle Dissection

Age 11 to 14
ShortChallenge Level Yellow starYellow star
Secondary curriculum
  • Problem
  • Solutions

The 16 by 9 rectangle is cut as shown.

16 by 9 rectangle cut into pieces

If the pieces are rearranged to form a square, what is the perimeter of the square?

If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
 

This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.

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Prove that a triangle with sides of length 5, 5 and 6 has the same area as a triangle with sides of length 5, 5 and 8. Find other pairs of non-congruent isosceles triangles which have equal areas.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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