Reflections

There are 60 NRICH Mathematical resources connected to Reflections
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?
Screen Shot
problem

Screen shot

Age
14 to 16
Challenge level
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A moveable screen slides along a mirrored corridor towards a centrally placed light source. A ray of light from that source is directed towards a wall of the corridor, which it strikes at 45 degrees before being reflected across to the opposite wall and so on until it hits the screen.
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.
Patchwork Quilt
problem

Patchwork quilt

Age
7 to 14
Challenge level
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Squares of the type shown are sewn together to make a quilt. How many different quilts can be made?
HexPentas
problem

Hexpentas

Age
5 to 11
Challenge level
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How many different ways can you find of fitting five hexagons together? How will you know you have found all the ways?
Penta Play
game

Penta play

A shape and space game for 2, 3 or 4 players. Be the last person to be able to place a pentomino piece on the playing board.
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?
Orbiting Billiard Balls
problem

Orbiting billiard balls

Age
14 to 16
Challenge level
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What angle is needed for a ball to do a circuit of the billiard table and then pass through its original position?
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?
Footprints
problem

Footprints

Age
16 to 18
Challenge level
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Make a footprint pattern using only reflections.