3/4 + 17/18 =

\[\frac{3}{4} + \frac{17}{18} = \frac{3 \times 9}{4 \times 9} + \frac{17 \times 2}{18 \times 2} = \frac{27}{36} + \frac{34}{36} = \frac{27+34}{36} = \frac{61}{36} = 1\frac{25}{36}\]