№1 Вычислите: 1) $$\frac{1}{5}+\frac{2}{5}$$ 2) $$\frac{3}{10}-\frac{1}{10}$$ 3) $$1\frac{1}{3}+\frac{1}{4}$$ 4) $$\frac{10}{5}+\frac{5}{6}$$ 5) $$2\frac{1}{6}-\frac{1}{6}$$ 6) $$1\frac{1}{2}+1\frac{1}{3}$$

Выполним вычисления: 1) $$\frac{1}{5}+\frac{2}{5}=\frac{1+2}{5}=\frac{3}{5}$$ 2) $$\frac{3}{10}-\frac{1}{10}=\frac{3-1}{10}=\frac{2}{10}=\frac{1}{5}$$ 3) $$1\frac{1}{3}+\frac{1}{4}=\frac{4}{3}+\frac{1}{4}=\frac{4*4+1*3}{12}=\frac{16+3}{12}=\frac{19}{12}=1\frac{7}{12}$$ 4) $$\frac{10}{5}+\frac{5}{6}=\frac{10*6+5*5}{30}=\frac{60+25}{30}=\frac{85}{30}=\frac{17}{6}=2\frac{5}{6}$$ 5) $$2\frac{1}{6}-\frac{1}{6}=2+\frac{1}{6}-\frac{1}{6}=2$$ 6) $$1\frac{1}{2}+1\frac{1}{3}=\frac{3}{2}+ \frac{4}{3}=\frac{3*3+4*2}{6}=\frac{9+8}{6}=\frac{17}{6}=2\frac{5}{6}$$ Ответ: 1) $$\frac{3}{5}$$; 2) $$\frac{1}{5}$$; 3) $$1\frac{7}{12}$$; 4) $$2\frac{5}{6}$$; 5) $$2$$; 6) $$2\frac{5}{6}$$