The Great Dodecahedron

What can you see hidden in plain sight?

This hexagon-shaped collection of triangles looks as though it could be a three-dimensional solid. Click triangles to hide them and double click to bring them back in order to complete the challenges below:

1

Remove some triangles to leave an equilateral triangle in the centre.

Check

2

Remove some triangles to leave a kite with a vertical line of symmetry.

Check

3

Remove some triangles to leave an irregular pentagon containing the three pink pieces.

Check

4

Remove some triangles to leave what looks like a tetrahedron viewed from above.

Check

5

Some people see the whole design as a cube. Remove some triangles to show the top of the cube.

Check

6

Remove all the pairs of triangles that prevent the design having a vertical line of symmetry due to their colours.

Check

7

Remove some triangles to leave what looks like a star on a blue pentagon.

Check

8

Remove some triangles to leave what looks like a star on a light green pentagon.

Check

9

Remove some triangles to leave what looks like a star on a dark green pentagon.

Check

Instructions

Try your best to answer the questions above. Type your answers into the boxes provided leaving no spaces. As you work through the exercise regularly click the "check" button. If you have any wrong answers, do your best to do corrections but if there is anything you don't understand, please ask your teacher for help.

When you have got all of the questions correct you may want to print out this page and paste it into your exercise book. If you keep your work in an ePortfolio you could take a screen shot of your answers and paste that into your Maths file.

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Transum,

Thursday, February 11, 2016

"The Great Dodecahedron poster was used to great effect on the Using and Applying Mathematics courses for teachers provided by Birmingham's Curriculum Support Service back in the day when Using and Applying Maths was seen to be a new concept!"

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