[tex]1\frac{3}{7}-\frac{6}{7} = \frac{10}{7}-\frac{6}{7} = \frac{4}{7}\\\\\frac{6}{7}+\boxed{\frac{4}{7}} = 1\frac{3}{7}[/tex]
[tex]2\frac{1}{4}-1\frac{3}{4} = 1\frac{5}{4}-1\frac{3}{4} = \frac{2}{4}\\\\1\frac{3}{4}+\boxed{\frac{2}{4}} = 2\frac{1}{4}[/tex]
[tex]19\frac{2}{5} - 17\frac{3}{7} = 18\frac{7}{5}-17\frac{3}{5} = 1\frac{4}{5}\\\\17\frac{3}{5}+\boxed{1\frac{4}{5}} = 19\frac{2}{5}[/tex]
[tex]7\frac{1}{8}-2\frac{3}{8} = 6\frac{9}{8}-2\frac{3}{8}=4\frac{6}{8}\\\\\boxed{4\frac{6}{8}}+2\frac{3}{8} = 7\frac{1}{8}[/tex]
[tex]5\frac{1}{11}-4\frac{9}{11} = 4\frac{12}{11}-4\frac{9}{11} = \frac{3}{11}\\\\\boxed{\frac{3}{11}}+4\frac{9}{11} = 5\frac{1}{11}[/tex]
[tex]19\frac{3}{6}-155\frac{4}{6} = 18\frac{9}{6} - 15\frac{4}{6} = 3\frac{5}{6}\\\\\boxed{3\frac{5}{6}}+15\frac{4}{6} = 19\frac{3}{6}[/tex]
