MathDB

8

Part of 2013 National Olympiad First Round

Problems(1)

P08 [Combinatorics] - Turkish NMO 1st Round - 2013

Source:

4/20/2013
How many kites are there such that all of its four vertices are vertices of a given regular icosagon (2020-gon)?
<spanclass=′latex−bold′>(A)</span> 105<spanclass=′latex−bold′>(B)</span> 100<spanclass=′latex−bold′>(C)</span> 95<spanclass=′latex−bold′>(D)</span> 90<spanclass=′latex−bold′>(E)</span> 85 <span class='latex-bold'>(A)</span>\ 105 \qquad<span class='latex-bold'>(B)</span>\ 100 \qquad<span class='latex-bold'>(C)</span>\ 95 \qquad<span class='latex-bold'>(D)</span>\ 90 \qquad<span class='latex-bold'>(E)</span>\ 85