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These resources have been reviewed and selected by STEM Learning’s team of education specialists for factual accuracy and relevance to teaching STEM subjects in UK schools.

Red Black Mind Meld

This magic trick from the Computer Science for Fun (CS4FN) team at QMUL is based on a ‘self-working trick’. It includes a set of instructions which, so long as the commands are followed, works every time. It is, therefore, an algorithm.

The trick involves playing cards – the actual value of the cards is not important, it is their position in the stack that is critical. The cards can therefore be ‘abstracted’. The trick goes on to employ logic and mathematics, fully explained in the document, to create a trick which seems to show people can influence the minds of others, telepathically!

The trick is verified by actually ‘running’ the algorithm, in a similar manner to how software is tested.

A series of extension tasks are included as well as links to other information.

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