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There are n pairs of shoes in a closet. If r(ltn) are selected at random then the number of ways that among the selected shoes there is atleast one pair is ""^(2n)C_(1).""^(n-1)C_(r-2).2^(r-2)

Answer» <html><body><p><br/></p><a href="https://interviewquestions.tuteehub.com/tag/answer-15557" style="font-weight:bold;" target="_blank" title="Click to know more about ANSWER">ANSWER</a> :`=""^(2n)C_(r)-""^(<a href="https://interviewquestions.tuteehub.com/tag/n-568463" style="font-weight:bold;" target="_blank" title="Click to know more about N">N</a>)C_(r)2^(r)`</body></html>


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