Essentially x0-x, where x is just a digit, not a number, will equal a multiple of 9.
That is sort of it, but going the wrong direction. 10x+x=11x; 11x-(x+x)=9x, by definition a multiple of 9. All other numbers between 10 and 99 are either:
10x+x+y, in which case 11x+y-(x+x+y)=9x, still a multiple of 9, or
10(x+y)+x, in which case 10x+10y+x-(x+x+y)=9x+9y, still a multiple of 9.
Honorbound and honored to be Bonded to Mahtaliel Sedai
Last First in wotmania Chat
Slightly better than chocolate.
Love still can't be coerced.
Please Don't Eat the Newbies!
LoL. Be well, RAFOlk.
Last First in wotmania Chat
Slightly better than chocolate.
Love still can't be coerced.
Please Don't Eat the Newbies!

LoL. Be well, RAFOlk.
Online magic trick: Lady Esmeralda's Crystal Ball
27/01/2012 10:27:29 AM
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I want to know how it works.
27/01/2012 10:48:28 AM
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I would tell you...
27/01/2012 11:02:43 AM
- 522 Views
No it wouldn't!
27/01/2012 11:37:18 AM
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If you really want to know, here it is.
27/01/2012 03:26:37 PM
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The key, it seems to me, is this:
27/01/2012 08:54:23 PM
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See, I knew someone would be able to do the actual mathematical thing.
27/01/2012 09:08:02 PM
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Math is just another language; the important thing is logic.
27/01/2012 09:46:23 PM
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