List

Perimeter and Area

Salinon
problem
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Salinon

Age
14 to 16
Challenge level
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This shape comprises four semi-circles. What is the relationship between the area of the shaded region and the area of the circle on AB as diameter?
Curvy areas
problem
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Curvy areas

Age
14 to 16
Challenge level
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Have a go at creating these images based on circles. What do you notice about the areas of the different sections?
Track design
problem
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Track design

Age
14 to 16
Challenge level
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Where should runners start the 200m race so that they have all run the same distance by the finish?

Arclets
problem
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Arclets

Age
14 to 16
Challenge level
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Each of the following shapes is made from arcs of a circle of radius r. What is the perimeter of a shape with 3, 4, 5 and n "nodes".
Triangles and petals
problem
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Triangles and petals

Age
14 to 16
Challenge level
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An equilateral triangle rotates around regular polygons and produces an outline like a flower. What are the perimeters of the different flowers?