Номер 805:выполните действия

2) $-1\frac{1}{7} ( \frac{4}{5} + \frac{19}{20} )*( 6\frac{5}{6} +4 \frac{2}{3} )=- \frac{8}{7}*( \frac{16}{20} + \frac{19}{20} )*( \frac{41}{6} + \frac{14}{3} ) \\ \\ =- \frac{8}{7} * \frac{35}{20} *( \frac{41}{6} + \frac{28}{6} )=-2* \frac{69}{6} =-23$
1) $2 \frac{1}{2} ( \frac{2}{15} -3 \frac{5}{6} )-2 \frac{3}{4} = \frac{5}{2} ( \frac{2}{15} - \frac{23}{6} )- \frac{11}{4} = \frac{5}{2} ( \frac{4}{30} - \frac{115}{30} )- \frac{11}{4} \\ \\ = \frac{5}{2} (- \frac{111}{30} )- \frac{11}{4} = -\frac{37}{4} - \frac{11}{4} =- \frac{48}{4} =-12 \\ \\$
3) $(6 \frac{3}{8} -2 \frac{3}{4} )*(-4)+ \frac{7}{18} *9=( \frac{51}{8} - \frac{11}{4} )*(-4)+ \frac{7}{2} = \\ \\ ( \frac{51}{8} - \frac{22}{8}) *(-4)+ \frac{7}{2} = \frac{29}{8} *(-4)+ \frac{7}{2} =- \frac{29}{2} + \frac{7}{2} =-11$
4) $9 \frac{1}{6} :(4 \frac{1}{3} -8)+24* \frac{3}{8} = \frac{55}{6} :(-3 \frac{2}{3} )+9= \frac{55}{6} *(- \frac{3}{11} )+9= \\ \\ -\frac{5}{2}+9=-2,5+9=6,5$