Упростите выражение: 1) $$\frac{5}{14}x - \frac{9}{28}x + \frac{11}{42}x$$; 2) $$8 \frac{13}{18}m - 4 \frac{7}{12}m + 5 \frac{5}{6}m$$.

Упростим данные выражения:

1) $$\frac{5}{14}x - \frac{9}{28}x + \frac{11}{42}x = ( \frac{5}{14} - \frac{9}{28} + \frac{11}{42})x = ( \frac{5 \cdot 6}{14 \cdot 6} - \frac{9 \cdot 3}{28 \cdot 3} + \frac{11 \cdot 2}{42 \cdot 2})x = ( \frac{30}{84} - \frac{27}{84} + \frac{22}{84})x = \frac{30 - 27 + 22}{84}x = \frac{25}{84}x$$

2) $$8 \frac{13}{18}m - 4 \frac{7}{12}m + 5 \frac{5}{6}m = (8 \frac{13}{18} - 4 \frac{7}{12} + 5 \frac{5}{6})m = (8 + \frac{13}{18} - 4 - \frac{7}{12} + 5 + \frac{5}{6})m = (8 - 4 + 5 + \frac{13}{18} - \frac{7}{12} + \frac{5}{6})m = (9 + \frac{13 \cdot 2}{18 \cdot 2} - \frac{7 \cdot 3}{12 \cdot 3} + \frac{5 \cdot 6}{6 \cdot 6})m = (9 + \frac{26}{36} - \frac{21}{36} + \frac{30}{36})m = (9 + \frac{26 - 21 + 30}{36})m = (9 + \frac{35}{36})m = 9 \frac{35}{36}m$$

Ответ: 1) $$\frac{25}{84}x$$; 2) $$9 \frac{35}{36}m$$