2017 AIME I Problem 5

A rational number written in base eight is \underline{a} \underline{b} . \underline{c} \underline{d}, where all digits are nonzero. The same number in base twelve is \underline{b} \underline{b} . \underline{b} \underline{a}. Find the base-ten number \underline{a} \underline{b} \underline{c}.