Symmetry

There are 72 NRICH Mathematical resources connected to Symmetry
Square pizza
problem

Square pizza

Age
14 to 16
Challenge level
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Can you show that you can share a square pizza equally between two people by cutting it four times using vertical, horizontal and diagonal cuts through any point inside the square?
Arclets
problem

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".
Prime Magic
problem

Prime Magic

Age
7 to 16
Challenge level
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Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?
Rhombicubocts
problem

Rhombicubocts

Age
11 to 14
Challenge level
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Each of these solids is made up with 3 squares and a triangle around each vertex. Each has a total of 18 square faces and 8 faces that are equilateral triangles. How many faces, edges and vertices does each solid have?
Encircling
problem

Encircling

Age
14 to 16
Challenge level
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An equilateral triangle is sitting on top of a square. What is the radius of the circle that circumscribes this shape?
Holly
problem

Holly

Age
14 to 16
Challenge level
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The ten arcs forming the edges of the "holly leaf" are all arcs of circles of radius 1 cm. Find the length of the perimeter of the holly leaf and the area of its surface.
Eight Dominoes
problem

Eight Dominoes

Age
7 to 16
Challenge level
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Using the 8 dominoes make a square where each of the columns and rows adds up to 8
A Problem of time
problem

A Problem of time

Age
14 to 16
Challenge level
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Consider a watch face which has identical hands and identical marks for the hours. It is opposite to a mirror. When is the time as read direct and in the mirror exactly the same between 6 and 7?
Witch of Agnesi
problem

Witch of Agnesi

Age
16 to 18
Challenge level
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Sketch the members of the family of graphs given by y = a^3/(x^2+a^2) for a=1, 2 and 3.
Maltese Cross
problem

Maltese Cross

Age
16 to 18
Challenge level
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Sketch the graph of $xy(x^2 - y^2) = x^2 + y^2$ consisting of four curves and a single point at the origin. Convert to polar form. Describe the symmetries of the graph.