2009 UNCO Math Contest II Problems/Problem 1

Revision as of 21:13, 19 October 2014 by Timneh (talk | contribs) (moved 2009 UNC Math Contest II Problems/Problem 1 to 2009 UNCO Math Contest II Problems/Problem 1: disambiguation of University of Northern Colorado with University of North Carolina)

Problem

How many positive $3$-digit numbers $abc$ are there such that $a+b=c$ For example, $202$ and $178$ have this property but $245$ and $317$ do not.


Solution

See also

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