MathNet 2016-part-05 — 184 problems (EN–VI) Question 164

Together, the two positive integers $a$ and $b$ have 9 digits and contain each of the digits $1$, $2$, $3$, $4$, $5$, $6$, $7$, $8$, $9$ exactly once. For which possible values of $a$ and $b$ is the fraction $a/b$ closest to $1$?