$\frac{1}{4}+\frac{1}{8}=\frac{2}{8}+\frac{1}{8}=\frac{3}{8}$  

$\frac{3}{4}-\frac{1}{8}=\frac{6}{8}-\frac{1}{8}=\frac{5}{8}$  

$\frac{1}{2}+\frac{1}{8}=\frac{4}{8}+\frac{1}{8}=\frac{5}{8}$  

$\frac{9}{8}-\frac{1}{8}=\frac{8}{8}=1$  

$\frac{2}{3}+\frac{1}{8}=\frac{16}{24}+\frac{3}{24}=\frac{19}{24}$  

$\frac{1}{3}-\frac{1}{8}=\frac{8}{24}-\frac{3}{24}=\frac{5}{24}$  

$\frac{5}{6}+\frac{1}{8}=\frac{20}{24}+\frac{3}{24}=\frac{23}{24}$  

$1\frac{1}{2}-\frac{1}{8}=1\frac{4}{8}-\frac{1}{8}=1\frac{3}{8}$  

$2\frac{1}{12}+\frac{1}{8}=2\frac{2}{24}+\frac{3}{24}=2\frac{5}{24}$  

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$\frac{1}{3}-\frac{1}{6}=\frac{2}{6}-\frac{1}{6}=\frac{1}{6}$  

$\frac{1}{2}+\frac{1}{6}=\frac{3}{6}+\frac{1}{6}=\frac{4}{6}=\frac{2}{3}$  

$\frac{11}{12}-\frac{1}{6}=\frac{11}{12}-\frac{2}{12}=\frac{9}{12}=\frac{3}{4}$  

$\frac{2}{3}+\frac{1}{6}=\frac{4}{6}+\frac{1}{6}=\frac{5}{6}$  

$1\frac{1}{4}-\frac{1}{6}=1\frac{3}{12}-\frac{2}{12}=1\frac{1}{12}$  

$2\frac{1}{4}+\frac{1}{6}=2\frac{3}{12}+\frac{2}{12}=2\frac{5}{12}$  

$7-\frac{1}{6}=6\frac{6}{6}-\frac{1}{6}=6\frac{5}{6}$  

$\frac{5}{9}+\frac{1}{6}=\frac{10}{18}+\frac{3}{18}=\frac{13}{18}$  

$3\frac{3}{8}-\frac{1}{6}=3\frac{9}{24}-\frac{4}{24}=3\frac{5}{24}$