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For younger learners

  • Early Years Foundation Stage

Perimeter and Area

Triangles in a Square

Age 11 to 14
Challenge Level Yellow star

What are the possible areas of triangles drawn in a square?

Blue and White

Age 11 to 14
Challenge Level Yellow star

Identical squares of side one unit contain some circles shaded blue. In which of the four examples is the shaded area greatest?

Fence It

Age 11 to 14
Challenge Level Yellow star

This problem challenges students to work systematically while applying their knowledge of areas of rectangles.

Isosceles Triangles

Age 11 to 14
Challenge Level Yellow star

This problem encourages students to use coordinates, area and isosceles triangles to solve a non-standard problem. To find all possible solutions they will need to work systematically.

Changing Areas, Changing Perimeters

Age 11 to 14
Challenge Level Yellow star

Working on this problem will give students a deeper understanding of area and perimeter, and how they change as a shape is altered.

Perimeter Challenge

Age 11 to 14
Challenge Level Yellow star

Can you deduce the perimeters of the shapes from the information given?

Perimeter Possibilities

Age 11 to 14
Challenge Level Yellow star

This problem combines both area and perimeter by inviting students to consider the different possibilities for the perimeter when the area of a rectangle is fixed.

Can They Be Equal?

Age 11 to 14
Challenge Level Yellow star

Sometimes area and perimeter of rectangles are taught separately, and are often confused. In this problem students consider the relationship between them.

On the Edge

Age 11 to 14
Challenge Level Yellow starYellow star

If you move the tiles around, can you make squares with different coloured edges?

An Unusual Shape

Age 11 to 14
Challenge Level Yellow starYellow star

This problem offers the opportunity to practise calculating areas of circles and fractions of a circle in the context of an optimisation task.

Warmsnug Double Glazing

Age 14 to 16
Challenge Level Yellow star

This problem offers students a chance to develop strategies for organising and understanding mixed up information within the context of calculating areas and perimeters of rectangles.

Pick's Theorem

Age 14 to 16
Challenge Level Yellow starYellow star

This problem allows students to consolidate their understanding of how to calculate the area of irregular shapes, while offering an opportunity to explore and discover an interesting result.

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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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