**"Similarity and enlargement"**

## Shadows Activity

*By toni On 1 May, 2021 · 2 Comments*

The picture shows some shadows cast by solid (3 dimensional) objects as well as some flat (2 dimensional) shapes.

Describe 3D objects that could have made these shadows. There is more than one answer for each shadow.

Can you draw different shadows that could be made by the same objects?

What sort of shadows […]

## Is a Square a Rectangle?

*By toni On 26 February, 2021 · 4 Comments*

Make a record of all the rectangles that you can find in this shape.

Which rectangles are exactly the same (congruent)?

Which rectangles are similar?

Is a Square a Rectangle – Template

Click here to download the IS A SQUARE A RECTANGLE? worksheet.

Click here to download the NOTES FOR TEACHERS.

[…]

## Sierpinski Number and Shape Patterns

*By toni On 16 November, 2020 · 2 Comments*

There are many investigations and projects you could do based on the Sierpinski Tetrahedron.

For a start: how many small tetrahedra, like the blue model shown, were used to make the 6.5 metre high red balloon model shown below.

The smallest tetrahedron (Stage 0), the blue model, is made from 6 balloons, each […]

## Fractions in a Square

*By toni On 18 April, 2020 · 4 Comments*

Squares 1, 2 and 3 all have edges of length 1 unit.

The top edge of square 2 is split into equal parts of length ½.

The left hand edge of square 3 is split into equal parts of length ½.

The top and bottom edges of square 3 is split into lengths ¼, […]

## Kite

*By toni On 27 July, 2018 · Leave a Comment*

Take a sheet of A4 paper. First fold the top left corner to meet the bottom edge and press the fold flat. Then fold the top right corner to meet the edge that you folded down.

Can you prove that the quadrilateral you have made is a kite?

Can you find the perimeter of the […]

Each picture shows 3 similar triangles.

They are called similar because they are the same shape, they have the same angles and the lengths of the edges are in the same ratio. For example in this diagram the edges in each triangle are all in the ratio 2 : 3 : 4 […]

## Flagpoles

*By toni On 9 March, 2013 · 2 Comments*

Two flagpoles are 30 metres apart. One has height 10 m and the other has height 15 m. Two tight ropes connect the top of each pole to the foot of the other.

How high do the two ropes intersect above the ground?

How many different methods can you find to solve this problem?

What […]

## Little Man

*By toni On 18 January, 2012 · Leave a Comment*

Little Man is much smaller than you and me. Here is a picture of him standing next to an ordinary mug.

Can you estimate how tall he is? How tall do you think Little Man’s mug might be?

My mug is 10 centimetres tall and it holds 300 millilitres but mugs come in different […]

## Tetrasquare

*By toni On 17 January, 2012 · Leave a Comment*

ABCD is a regular tetrahedron and the points P, Q, R and S

are the midpoints of the edges AB, BD, CD and CA.

Prove that PQRS is a square.

What does this tell you about the opposite edges of the tetrahedron?

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