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Contests
National and Regional Contests
Iran Contests
Iran MO (1st Round)
2018 Iran MO (1st Round)
13
13
Part of
2018 Iran MO (1st Round)
Problems
(1)
Rest in peace, Bahman - Iran First Round 2018, P13
Source:
3/7/2021
Bahman wants to build an area next to his garden's wall for keeping his poultry. He has three fences each of length
10
10
10
meters. Using the garden's wall, which is straight and long, as well as the three pieces of fence, what is the largest area Bahman can enclose in meters squared?
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300
<span class='latex-bold'>(A)</span>\ 100 \qquad<span class='latex-bold'>(B)</span>\ 50+25 \sqrt 3\qquad<span class='latex-bold'>(C)</span>\ 50 + 50\sqrt 2\qquad<span class='latex-bold'>(D)</span>\ 75 \sqrt 3 \qquad<span class='latex-bold'>(E)</span>\ 300
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50
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300
geometric optimization