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Problems
Contests
National and Regional Contests
Canada Contests
Gauss
1999 Gauss
11
11
Part of
1999 Gauss
Problems
(1)
1999 Gauss (7) #11
Source:
7/6/2011
The floor of a rectangular room is covered with square tiles. The room is 10 tiles long and 5 tiles wide. The number of tiles that touch the walls of the room is
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26
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30
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C
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34
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D
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46
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<span class='latex-bold'>(A)</span>\ 26 \qquad <span class='latex-bold'>(B)</span>\ 30 \qquad <span class='latex-bold'>(C)</span>\ 34 \qquad <span class='latex-bold'>(D)</span>\ 46 \qquad <span class='latex-bold'>(E)</span>\ 50
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30
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34
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46
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50
Gauss
geometry
perimeter