1) 1 5 + 2 5 = 3 5 {\displaystyle {\frac {1}{5}}+{\frac {2}{5}}={\frac {3}{5}}}
2) 1 2 + 1 2 = 1 {\displaystyle {\frac {1}{2}}+{\frac {1}{2}}=1}
3) 2 3 + 5 3 = 7 3 {\displaystyle {\frac {2}{3}}+{\frac {5}{3}}={\frac {7}{3}}}
4) 2 6 + 1 6 = 1 2 {\displaystyle {\frac {2}{6}}+{\frac {1}{6}}={\frac {1}{2}}}
5) 9 20 + 3 20 = 3 5 {\displaystyle {\frac {9}{20}}+{\frac {3}{20}}={\frac {3}{5}}}
6) 6 35 + 18 35 = 24 35 {\displaystyle {\frac {6}{35}}+{\frac {18}{35}}={\frac {24}{35}}}
7) 5 12 + 1 12 = 1 2 {\displaystyle {\frac {5}{12}}+{\frac {1}{12}}={\frac {1}{2}}}
8) 13 16 + 19 16 = 2 {\displaystyle {\frac {13}{16}}+{\frac {19}{16}}=2}
9) 11 7 + 2 7 = 13 7 {\displaystyle {\frac {11}{7}}+{\frac {2}{7}}={\frac {13}{7}}}
10) 10 21 + 4 21 = 2 3 {\displaystyle {\frac {10}{21}}+{\frac {4}{21}}={\frac {2}{3}}}