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Contests
National and Regional Contests
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MAA AMC
AMC 8
2005 AMC 8
8
8
Part of
2005 AMC 8
Problems
(1)
AMC 8 2005 Problem 8
Source:
7/23/2011
Suppose m and n are positive odd integers. Which of the following must also be an odd integer?
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<span class='latex-bold'>(A)</span>\ m+3n\qquad<span class='latex-bold'>(B)</span>\ 3m-n\qquad<span class='latex-bold'>(C)</span>\ 3m^2 + 3n^2\qquad<span class='latex-bold'>(D)</span>\ (nm + 3)^2\qquad<span class='latex-bold'>(E)</span>\ 3mn
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