226. Сократите: 1) $$rac{12\cdot21}{35\cdot15}$$; 2) $$rac{72\cdot11}{33\cdot30}$$; 3) $$rac{25\cdot17\cdot44}{51\cdot8\cdot75}$$; 4) $$rac{8\cdot3+8\cdot23}{3\cdot16}$$; 5) $$rac{17\cdot48}{17\cdot16-9\cdot16}$$; 6) $$rac{14\cdot5-14\cdot3}{21\cdot9+21\cdot3}$$.

Решим примеры по порядку: 1) $$rac{12\cdot21}{35\cdot15} = \frac{3\cdot4\cdot3\cdot7}{5\cdot7\cdot3\cdot5} = \frac{3\cdot4}{5\cdot5} = \frac{12}{25}$$ 2) $$rac{72\cdot11}{33\cdot30} = \frac{11\cdot6\cdot12}{11\cdot3\cdot6\cdot5} = \frac{12}{3\cdot5} = \frac{3\cdot4}{3\cdot5} = \frac{4}{5}$$ 3) $$rac{25\cdot17\cdot44}{51\cdot8\cdot75} = \frac{25\cdot17\cdot4\cdot11}{17\cdot3\cdot8\cdot25\cdot3} = \frac{4\cdot11}{3\cdot8\cdot3} = \frac{4\cdot11}{3\cdot4\cdot2\cdot3} = \frac{11}{18}$$ 4) $$rac{8\cdot3+8\cdot23}{3\cdot16} = \frac{8\cdot(3+23)}{3\cdot16} = \frac{8\cdot26}{3\cdot16} = \frac{8\cdot2\cdot13}{3\cdot8\cdot2} = \frac{13}{3}$$ 5) $$rac{17\cdot48}{17\cdot16-9\cdot16} = \frac{17\cdot48}{16\cdot(17-9)} = \frac{17\cdot3\cdot16}{16\cdot8} = \frac{17\cdot3}{8} = \frac{51}{8}$$ 6) $$rac{14\cdot5-14\cdot3}{21\cdot9+21\cdot3} = \frac{14\cdot(5-3)}{21\cdot(9+3)} = \frac{14\cdot2}{21\cdot12} = \frac{7\cdot2\cdot2}{7\cdot3\cdot3\cdot4} = \frac{4}{3\cdot3\cdot4} = \frac{1}{9}$$