Question 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 $\underline{a}\,\underline{b}\,\underline{c}.$