Question 1106657
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So, Edwin's elegant solution confirmed my results that are under this link


<A HREF=https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1106687.html>https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1106687.html</A>


https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1106687.html



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To make your horizon wider, look into the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF =http://www.algebra.com/algebra/homework/Permutations/Problems-on-Permutations.lesson>Problems on Permutations</A>, Problem 5

in this site.