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2010 UNCO Math Contest II Problems/Problem 5

Revision as of 15:17, 19 October 2014 by Timneh (talk | contribs) (Created page with "== Problem == (a) In the <math>4 \times 4</math> grid shown, four coins are randomly placed in different squares. What is the probability that no two coins lie in the same row ...")
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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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