Запишите недостающие числа.
а) $\frac{5}{7} + \frac{1}{7} = \frac{}{7}$
б) $\frac{3}{8} + \frac{2}{8} = \frac{}{8}$
в) $\frac{4}{11} + \frac{5}{11} = \frac{}{11}$
г) $\frac{5}{6} - \frac{3}{6} = \frac{}{6}$
д) $\frac{3}{4} - \frac{2}{4} = \frac{}{4}$
е) $\frac{5}{10} - \frac{5}{10} = ...$
ж) $\frac{2}{3} + \frac{1}{3} = ...$
з) $\frac{8}{13} - \frac{5}{13} = \frac{}{13}$
и) $\frac{9}{9} - \frac{1}{9} = \frac{}{9}$

$\frac{5}{7} + \frac{1}{7} = \frac{6}{7}$
$\frac{3}{8} + \frac{2}{8} = \frac{5}{8}$
$\frac{4}{11} + \frac{5}{11} = \frac{9}{11}$
$\frac{5}{6} - \frac{3}{6} = \frac{2}{6}$
$\frac{3}{4} - \frac{2}{4} = \frac{1}{4}$
$\frac{5}{10} - \frac{5}{10} = 0$
$\frac{2}{3} + \frac{1}{3} = \frac{3}{3} = 1$
$\frac{8}{13} - \frac{5}{13} = \frac{3}{13}$
$\frac{9}{9} - \frac{1}{9} = \frac{8}{9}$