Mind Reading!

chip

Well-known member
  • Jul 25, 2006
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    Anusha said:
    Here's the proof.

    Say the number you imagined was XY (i.e. if X=4 and Y=3, XY=43).
    But if you write it mathematically, it's X*10+Y (in the previous example, 4*10+3 = 43, see?)
    Now it asks you to add the two digits ==> (X+Y)
    Now let's substract it from X*10+Y==>

    X * 10 + Y - (X + Y)
    =X * 10 + Y - X - Y
    =X * 9 ==> is always a multiple of 9.

    The answer is always a multiple of 9.


    Now you get it?

    yup...it workd this time..lolzz....:D