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2012 AMC 12B Question 25

AMC12 · 2012 AMC 12B

Question 25

Let $S = \{(x, y) : x \in \{0, 1, 2, 3, 4\},$ $y \in \{0, 1, 2, 3, 4, 5\},$ and $(x, y) \ne (0, 0)\}.$ Let $T$ be the set of all right triangles whose vertices are in $S.$ For every right triangle $t = \triangle ABC$ with vertices $A,$ $B,$ and $C$ in counter-clockwise order and right angle at $A,$ let $f(t) = \tan(\angle CBA).$ What is $$
\prod_{t \in T} f(t)?
$$
  1. $1$
  2. $\dfrac{625}{144}$
  3. $\dfrac{125}{24}$
  4. $6$
  5. $\dfrac{625}{24}$