Реши уравнения: a) 3$$\frac{7}{12}$$ + y = 6$$\frac{20}{3}$$; б) 8$$\frac{2}{7}$$ - x = 4$$\frac{13}{18}$$

a) $$3\frac{7}{12} + y = 6\frac{20}{3}$$

$$y = 6\frac{20}{3} - 3\frac{7}{12} = 6 + \frac{20}{3} - 3 - \frac{7}{12} = 3 + \frac{80 - 7}{12} = 3 + \frac{73}{12} = 3 + 6\frac{1}{12} = 9\frac{1}{12}$$

Ответ: $$9\frac{1}{12}$$

б) $$8\frac{2}{7} - x = 4\frac{13}{18}$$

$$x = 8\frac{2}{7} - 4\frac{13}{18} = 4 + \frac{2}{7} - \frac{13}{18} = 4 + \frac{36 - 91}{126} = 4 - \frac{55}{126} = 3\frac{126 - 55}{126} = 3\frac{71}{126}$$

Ответ: $$3\frac{71}{126}$$