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National and Regional Contests
Turkey Contests
National Olympiad First Round
2002 National Olympiad First Round
15
15
Part of
2002 National Olympiad First Round
Problems
(1)
P15 [Combinatorics] - Turkish NMO 1st Round - 2002
Source:
8/8/2014
There are
10
10
10
seats in each of
10
10
10
rows of a theatre and all the seats are numbered. What is the probablity that two friends buying tickets independently will occupy adjacent seats?
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55
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25
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None of above
<span class='latex-bold'>a)</span>\ \dfrac{1}{55} \qquad<span class='latex-bold'>b)</span>\ \dfrac{1}{50} \qquad<span class='latex-bold'>c)</span>\ \dfrac{2}{55} \qquad<span class='latex-bold'>d)</span>\ \dfrac{1}{25} \qquad<span class='latex-bold'>e)</span>\ \text{None of above}
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None of above
probability