Question 109
Suppose $N$ is a 6-digit number having base-10 representation $\underline{a}\ \underline{b}\ \underline{c}\ \underline{d}\ \underline{e}\ \underline{f}$. If $N$ is $6/7$ of the number having base-10 representation $\underline{d}\ \underline{e}\ \underline{f}\ \underline{a}\ \underline{b}\ \underline{c}$, find $N$.