I've found this question and tried to solve it, but failed
If a,b,c are positive and integers, $a+\frac{1}{b+\frac{1}{c}}=\frac{25}{19}$, then $a+b+c=?$ and how to get it?
On
$\begin{eqnarray*} \frac{25}{19} &=& 1+\frac{6}{19} \\[5pt] &=& 1+\frac{1}{\frac{19}{6}} \\[5pt] &=& 1+\frac{1}{3+\frac{1}{6}} \\ \end{eqnarray*}$
$\therefore a+b+c=1+3+6=10$
P.S. The above work shows the existence of $a,b,c$. For the uniqueness see also Ex. 1 on p.3 of http://www.math.hawaii.edu/~pavel/contfrac.pdf
Hint:
$$a < a+\frac{1}{b+\frac1c} <a+1$$
Then do the same with $$b < b+\frac1c \leq b+1$$