#### Explanation:

As A, B and C, each working alone complete a job in $6$, $8$ and $12$ days, respectively, they do $\frac{1}{6}$, $\frac{1}{8}$ and $\frac{1}{12}$ of the job in a day.

Hence they together do $\frac{1}{6} + \frac{1}{8} + \frac{1}{12} = \frac{4}{24} + \frac{3}{24} + \frac{2}{24} = \frac{9}{24} = \frac{3}{8}$ of the job in one day or complete the job in $\frac{8}{3} = 2 \frac{2}{3}$ days.

Note that work done by them is in the ratio $\frac{1}{6} : \frac{1}{8} : \frac{1}{12} \Leftrightarrow \frac{4}{24} : \frac{3}{24} : \frac{2}{24} \Leftrightarrow 4 : 3 : 2$.

As the work done by them is in the ratio of $4 : 3 : 2$ (their sum is $4 + 3 + 2 = 9$),

C's share in earnings will be $2340xx2/9=260cancel(2340)xx2/(1cancel9)=$520.