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National and Regional Contests
Turkey Contests
National Olympiad First Round
2007 National Olympiad First Round
36
36
Part of
2007 National Olympiad First Round
Problems
(1)
Turkey NMO 2007 1st Round - P36 (Combinatorics)
Source:
10/5/2012
Five points, no three of which are collinear, are given. What is the least possible value of the numbers of convex polygons whose some corners are from these five points?
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11
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<span class='latex-bold'>(A)</span>\ 10 \qquad<span class='latex-bold'>(B)</span>\ 11 \qquad<span class='latex-bold'>(C)</span>\ 12 \qquad<span class='latex-bold'>(D)</span>\ 15 \qquad<span class='latex-bold'>(E)</span>\ 16
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11
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16