Сравнить дроби, найти их суммы и разности:

1) $\frac{13}{20} > \frac{7}{20}$ (13 > 7); $\frac{13}{20} + \frac{7}{20} = \frac{20}{20} = 1$; $\frac{13}{20} - \frac{7}{20} = \frac{6}{20} = \frac{3}{10}$ 2) $\frac{4}{15} < \frac{8}{15}$ (4 < 8); $\frac{4}{15} + \frac{8}{15} = \frac{12}{15} = \frac{4}{5}$; $\frac{8}{15} - \frac{4}{15} = \frac{4}{15}$ 3) $\frac{13}{19} < \frac{15}{19}$ (13 < 15); $\frac{13}{19} + \frac{15}{19} = \frac{28}{19} = 1 \frac{9}{19}$; $\frac{15}{19} - \frac{13}{19} = \frac{2}{19}$ 4) $\frac{5}{11} > \frac{3}{11}$ (5 > 3); $\frac{5}{11} + \frac{3}{11} = \frac{8}{11}$; $\frac{5}{11} - \frac{3}{11} = \frac{2}{11}$ 5) $1 \frac{5}{12} > \frac{5}{12}$ ($\frac{17}{12} > \frac{5}{12}$); $1 \frac{5}{12} + \frac{5}{12} = 1 \frac{10}{12} = 1 \frac{5}{6}$; $1 \frac{5}{12} - \frac{5}{12} = 1$ 6) $\frac{15}{61} > \frac{9}{61}$ (15 > 9); $\frac{15}{61} + \frac{9}{61} = \frac{24}{61}$; $\frac{15}{61} - \frac{9}{61} = \frac{6}{61}$ 7) $\frac{7}{33} < \frac{28}{33}$ (7 < 28); $\frac{7}{33} + \frac{28}{33} = \frac{35}{33} = 1 \frac{2}{33}$; $\frac{28}{33} - \frac{7}{33} = \frac{21}{33} = \frac{7}{11}$ 8) $\frac{4}{27} < \frac{18}{27}$ (4 < 18); $\frac{4}{27} + \frac{18}{27} = \frac{22}{27}$; $\frac{18}{27} - \frac{4}{27} = \frac{14}{27}$ 9) $\frac{19}{25} > \frac{13}{25}$ (19 > 13); $\frac{19}{25} + \frac{13}{25} = \frac{32}{25} = 1 \frac{7}{25}$; $\frac{19}{25} - \frac{13}{25} = \frac{6}{25}$ 10) $7 \frac{2}{7} > 1 \frac{3}{7}$ ($\frac{51}{7} > \frac{10}{7}$); $7 \frac{2}{7} + 1 \frac{3}{7} = 8 \frac{5}{7}$; $7 \frac{2}{7} - 1 \frac{3}{7} = 6 \frac{9}{7} - 1 \frac{3}{7} = 5 \frac{6}{7}$ 11) $\frac{29}{103} > \frac{28}{103}$ (29 > 28); $\frac{29}{103} + \frac{28}{103} = \frac{57}{103}$; $\frac{29}{103} - \frac{28}{103} = \frac{1}{103}$ 12) $\frac{107}{152} < \frac{213}{152}$ (107 < 213); $\frac{107}{152} + \frac{213}{152} = \frac{320}{152} = 2 \frac{16}{152} = 2 \frac{2}{19}$; $\frac{213}{152} - \frac{107}{152} = \frac{106}{152} = \frac{53}{76}$ 13) $\frac{15}{143} < \frac{29}{143}$ (15 < 29); $\frac{15}{143} + \frac{29}{143} = \frac{44}{143} = \frac{4}{13}$; $\frac{29}{143} - \frac{15}{143} = \frac{14}{143}$ 14) $\frac{11}{201} > \frac{5}{201}$ (11 > 5); $\frac{11}{201} + \frac{5}{201} = \frac{16}{201}$; $\frac{11}{201} - \frac{5}{201} = \frac{6}{201} = \frac{2}{67}$ 15) $1 \frac{1}{9} < 2 \frac{4}{9}$ ($\frac{10}{9} < \frac{22}{9}$); $1 \frac{1}{9} + 2 \frac{4}{9} = 3 \frac{5}{9}$; $2 \frac{4}{9} - 1 \frac{1}{9} = 1 \frac{3}{9} = 1 \frac{1}{3}$