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1 . Let $n \geq 1$ be an integer. Consider a uniformly random permutation of the set $\{1,2,3,\dots,2n\}$. Define the event
  • A = "both the first element and the last element in the permutation are even integers".
What is $\Pr(A)$?
(a)
$\frac{2(2n-1)}{n-1}$
(b)
$\frac{n-1}{4n}$
(c)
$\frac{n-1}{2(2n-1)}$
(d)
$\frac{n}{2(2n-1)}$