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Take a Square

Age 14 to 16
Challenge Level Yellow starYellow starYellow star
  • Problem
  • Getting Started
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Cut off three congruent right angled isosceles triangles to produce a pentagon.

With two lines, cut the pentagon into three parts which can be rearranged into another square.

A square with three isosceles triangles removed from three corners to form a pentagon

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Compare Areas

Which has the greatest area, a circle or a square, inscribed in an isosceles right angle triangle?

Semi-detached

A square of area 40 square cms is inscribed in a semicircle. Find the area of the square that could be inscribed in a circle of the same radius.

Diagonal Touch

Weekly Problem 21 - 2012
Two rectangles are drawn in a rectangle. What fraction of the rectangle is shaded?

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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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