Magic chrystal ball

If you are out of ideas for how to push your kid into learning maths, maybe this Magic Chrystal Ball game will help. It is simple and effective, while being fun. Requires Macromedia Flash though.

3 thoughts on “Magic chrystal ball”


  1. As leonid correctly guessed and I expanded his guess,
    (A*10+B)-(A+B) = 10A+B-A-B = 9A

    which always gives out numbers divisible by 9.

    How about games with integrals and derivatives next time?

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