63. Упростите выражение: 1) $$\frac{3}{14}x - \frac{4}{21}x + \frac{7}{28}x$$; 2) $$3\frac{1}{6}y + 2\frac{7}{16}y - 4\frac{11}{12}y$$.

1. $$\frac{3}{14}x - \frac{4}{21}x + \frac{7}{28}x=(\frac{3}{14} - \frac{4}{21} + \frac{7}{28})x = (\frac{18-16+21}{84})x=\frac{23}{84}x$$
2. $$3\frac{1}{6}y + 2\frac{7}{16}y - 4\frac{11}{12}y = (3\frac{1}{6} + 2\frac{7}{16} - 4\frac{11}{12})y = (\frac{19}{6} + \frac{39}{16} - \frac{59}{12})y = (\frac{152+117-236}{48})y = (\frac{33}{48})y = \frac{11}{16}y$$

Ответ: 1) $$\frac{23}{84}x$$; 2) $$\frac{11}{16}y$$