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2010 UNCO Math Contest II Problems/Problem 5

Revision as of 20:17, 19 October 2014 by Timneh (talk | contribs) (moved 2010 UNC Math Contest II Problems/Problem 5 to 2010 UNCO Math Contest II Problems/Problem 5: disambiguation of University of Northern Colorado with University of North Carolina)

Problem

(a) In the $4 \times 4$ grid shown, four coins are randomly placed in different squares. What is the probability that no two coins lie in the same row or column?

$\begin{tabular}{|c|c|c|c|} \hline &&& \\ \hline &&& \\ \hline &&& \\ \hline &&& \\ \hline \end{tabular}$

(b) Generalize this to an $N \times N$ grid.


Solution

See also

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