Maths Workshop




A standard envelope

An unusual rectangular envelope

A parallelogram-shaped envelope

Reviewing geometry in rectangular envelopes



An envelope is an object which is used a lot in everyday life. We have all used envelopes to put letters or important documents into and as students we have often had to use them.

However, as well as being very useful objects, envelopes are also interesting to analyse from a mathematical point of view. Their geometrical shape is of interest firstly to people who have to make them and secondly to maths students who can use them to review a few interesting concepts such as line symmetry and similarity.  

I hope you enjoy playing with these envelopes and discovering the maths contained "inside them".

  • Discover the shape used to make a rectangular envelope when it is unfolded.

  • Discover other possible types of rectangular envelopes.

  • Discover non-rectangular envelopes.

  • From the final dimensions of a finished envelope be able to illustrate the making of that envelope step by step and then actually make it.

  • Review the geometry involved in a rectangular envelope.

  Ángel Cabezudo Bueno
Spanish Ministry of Education. Year 2001

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