First, least common multiple must be found. To do this the numerator and denominator of 1/9 must be multiplied by 2 and the numerator and denominator of 5/6 must be multiplied by 3 to give 2/18 + 15/18. Then the two fractions (2/18 and 15/18) can be added together to give 17/18. Final Answer: 17/18.