Выполни вычисления в задании 19

- a) $6\frac{1}{3} - 8 = \frac{19}{3} - 8 = \frac{19 - 24}{3} = -\frac{5}{3} = -1\frac{2}{3}$ - б) $-2\frac{2}{7} + 4\frac{3}{5} = -\frac{16}{7} + \frac{23}{5} = \frac{-16 \cdot 5 + 23 \cdot 7}{35} = \frac{-80 + 161}{35} = \frac{81}{35} = 2\frac{11}{35}$ - в) $5\frac{1}{3} - 6\frac{1}{4} = \frac{16}{3} - \frac{25}{4} = \frac{16 \cdot 4 - 25 \cdot 3}{12} = \frac{64 - 75}{12} = -\frac{11}{12}$ - г) $3\frac{8}{9} : (-\frac{16}{9}) = \frac{35}{9} : (-\frac{16}{9}) = \frac{35}{9} \cdot (-\frac{9}{16}) = -\frac{35}{16} = -2\frac{3}{16}$ - д) $\frac{5}{12} \cdot (-6) = \frac{5 \cdot (-6)}{12} = \frac{-30}{12} = -\frac{5}{2} = -2.5$ - е) $-3\frac{2}{9} \cdot 3 = -\frac{29}{9} \cdot 3 = -\frac{29 \cdot 3}{9} = -\frac{29}{3} = -9\frac{2}{3}$ - ж) $\frac{4}{7} \cdot (-49) = \frac{4 \cdot (-49)}{7} = 4 \cdot (-7) = -28$ - з) $-16 : (-\frac{4}{9}) = -16 \cdot (-\frac{9}{4}) = \frac{-16 \cdot (-9)}{4} = 4 \cdot 9 = 36$ - и) $-3\frac{1}{2} : (-1\frac{1}{3}) = -\frac{7}{2} : (-\frac{4}{3}) = -\frac{7}{2} \cdot (-\frac{3}{4}) = \frac{7 \cdot 3}{2 \cdot 4} = \frac{21}{8} = 2\frac{5}{8}$