Math Trick

Hopefully you know how these tricks work already. It takes non-mathies a LONG time to discover how the following trick works!! (and usually they have to ask one of us to figure it out):

flash mind reader

Flash Mind Reader

Regifting robin

Regifting Robin

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  1. You have 10a + b – a – b = 9a, so you need to have the same result for all multiples of nine (9, 18, 27, …)

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  2. My students never figured out how the crystal ball read their minds. They thought there was a microphone on my laptop cart, so I started speaking in code and misdirection. Then they claimed it was photo-sensitive (although they didn’t use that term) because I was making shadows on the screen (not a Smart Board, mind you). Fun times.

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  3. It’s simple all the numbers you will get will have the symbol like the one on 9. Because they gave that symbol to every possible outcome.

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