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National and Regional Contests
Iran Contests
Iran MO (1st Round)
2018 Iran MO (1st Round)
4
4
Part of
2018 Iran MO (1st Round)
Problems
(1)
Five points in the plane - Iran First Round 2018, P4
Source:
3/6/2021
There are
5
5
5
points in the plane no three of which are collinear. We draw all the segments whose vertices are these points. What is the minimum number of new points made by the intersection of the drawn segments?
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0
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1
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2
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D
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3
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5
<span class='latex-bold'>(A)</span>\ 0\qquad<span class='latex-bold'>(B)</span>\ 1\qquad<span class='latex-bold'>(C)</span>\ 2\qquad<span class='latex-bold'>(D)</span>\ 3\qquad<span class='latex-bold'>(E)</span>\ 5
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1
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2
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3
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5
points