2002 AMC 10A Problem 2

$$\begin{aligned} (2,12,9) &= \dfrac{2}{12}+\dfrac{12}{9}+\dfrac{9}{2} \\ &= \dfrac{1}{6}+\dfrac{4}{3}+\dfrac{9}{2}. \end{aligned}$$ Over a denominator of $6,$ this is $\dfrac{1+8+27}{6}=\dfrac{36}{6}=6.$ Thus, the correct answer is C.