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Who is the fairest of them all ?

Age 11 to 14
Challenge Level Yellow starYellow starYellow star
Secondary curriculum
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Who is the fairest of them all? printable sheet
 
 
This problem is the third of three related problems. The first problem is Mirror, Mirror... , and the second is ...on the Wall.
 
 
Flag with two centres of enlargement


You might find it helpful to copy the diagram onto dotty paper.

Enlarge the flag by a scale factor of $2$ about the first centre of enlargement. Now enlarge the resulting flag by a scale factor of $\frac{1}{2}$ about the second centre of enlargement. Can you find a single transformation that takes the first flag to the last flag?

Try this with the flag in different positions, and with different centres of enlargement. Describe what will happen for any two centres of enlargement and a flag in any position.

Now try changing the scale factors so that the first enlargement is by scale factor $3$ and the second by scale factor $\frac{1}{3}$. Try some other similar pairs (remembering that if the first scale factor is $k$ then the second one should be $\frac{1}{k}$).

Describe what will happen if the first scale factor is $k$ and the second $\frac{1}{k}$?

 

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Explain how the thirteen pieces making up the regular hexagon shown in the diagram can be re-assembled to form three smaller regular hexagons congruent to each other.

Transformation Game

Why not challenge a friend to play this transformation game?

Growing Rectangles

What happens to the area and volume of 2D and 3D shapes when you enlarge them?

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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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