Reflections

There are 58 NRICH Mathematical resources connected to Reflections
Rots and Refs
problem

Rots and Refs

Age
16 to 18
Challenge level
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Follow hints using a little coordinate geometry, plane geometry and trig to see how matrices are used to work on transformations of the plane.
Clocks
problem

Clocks

Age
7 to 11
Challenge level
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These clocks have been reflected in a mirror. What times do they say?
Snookered
problem

Snookered

Age
14 to 18
Challenge level
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In a snooker game the brown ball was on the lip of the pocket but it could not be hit directly as the black ball was in the way. How could it be potted by playing the white ball off a cushion?
Transformation Tease
problem

Transformation Tease

Age
7 to 11
Challenge level
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What are the coordinates of this shape after it has been transformed in the ways described? Compare these with the original coordinates. What do you notice about the numbers?
Tricircle
problem

Tricircle

Age
14 to 16
Challenge level
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The centre of the larger circle is at the midpoint of one side of an equilateral triangle and the circle touches the other two sides of the triangle. A smaller circle touches the larger circle and two sides of the triangle. If the small circle has radius 1 unit find the radius of the larger circle.
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?
Retracircles
problem

Retracircles

Age
16 to 18
Challenge level
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Four circles all touch each other and a circumscribing circle. Find the ratios of the radii and prove that joining 3 centres gives a 3-4-5 triangle.
Cushion Ball
problem

Cushion Ball

Age
16 to 18
Challenge level
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The shortest path between any two points on a snooker table is the straight line between them but what if the ball must bounce off one wall, or 2 walls, or 3 walls?
Star Find
problem

Star Find

Age
5 to 7
Challenge level
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Can you see which tile is the odd one out in this design? Using the basic tile, can you make a repeating pattern to decorate our wall?
Times
problem

Times

Age
7 to 11
Challenge level
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Which times on a digital clock have a line of symmetry? Which look the same upside-down? You might like to try this investigation and find out!