Si les fraccions tenen el mateix denominador, la suma és una fracció d'igual denominador i numerador suma de numeradors.
1) 1 5 + 2 5 = 3 5 {\displaystyle {\frac {1}{5}}+{\frac {2}{5}}={\frac {3}{5}}}
2) 1 2 + 1 2 = {\displaystyle {\frac {1}{2}}+{\frac {1}{2}}=}
3) 2 3 + 5 3 = {\displaystyle {\frac {2}{3}}+{\frac {5}{3}}=}
4) 2 6 + 1 6 = {\displaystyle {\frac {2}{6}}+{\frac {1}{6}}=}
5) 9 20 + 3 20 = {\displaystyle {\frac {9}{20}}+{\frac {3}{20}}=}
6) 6 35 + 18 35 = {\displaystyle {\frac {6}{35}}+{\frac {18}{35}}=}
7) 5 12 + 1 12 = {\displaystyle {\frac {5}{12}}+{\frac {1}{12}}=}
8) 13 16 + 19 16 = {\displaystyle {\frac {13}{16}}+{\frac {19}{16}}=}
9) 11 7 + 2 7 = {\displaystyle {\frac {11}{7}}+{\frac {2}{7}}=}
10) 10 21 + 4 21 = {\displaystyle {\frac {10}{21}}+{\frac {4}{21}}=}
solucions