1). 2 1/3 : (5/8 - 8/3) - 2 * 1 3/7

Привет! Давай решим примеры по порядку. Вот решения: 1) $2\frac{1}{3} : (\frac{5}{8} - \frac{8}{3}) - 2 \cdot 1\frac{3}{7} = \frac{7}{3} : (\frac{15}{24} - \frac{64}{24}) - 2 \cdot \frac{10}{7} = \frac{7}{3} : (-\frac{49}{24}) - \frac{20}{7} = \frac{7}{3} \cdot (-\frac{24}{49}) - \frac{20}{7} = -\frac{8}{7} - \frac{20}{7} = -\frac{28}{7} = -4$ 2) $\frac{7}{15} : (\frac{6}{10} - \frac{8}{3}) + 19 \cdot \frac{2}{31} = \frac{7}{15} : (\frac{9}{15} - \frac{40}{15}) + \frac{38}{31} = \frac{7}{15} : (-\frac{31}{15}) + \frac{38}{31} = -\frac{7}{31} + \frac{38}{31} = \frac{31}{31} = 1$ 3) $(7 - 1\frac{5}{9} : \frac{7}{24}) : \frac{20}{27} = (7 - \frac{14}{9} \cdot \frac{24}{7}) : \frac{20}{27} = (7 - \frac{2}{3} \cdot \frac{8}{1}) : \frac{20}{27} = (7 - \frac{16}{3}) : \frac{20}{27} = \frac{5}{3} \cdot \frac{27}{20} = \frac{9}{4} = 2,25$ 4) $(1\frac{1}{35} : \frac{4}{5} - 1\frac{8}{35}) \cdot 3\frac{1}{3} = (\frac{36}{35} \cdot \frac{5}{4} - \frac{43}{35}) \cdot \frac{10}{3} = (\frac{9}{7} - \frac{43}{35}) \cdot \frac{10}{3} = (\frac{45-43}{35}) \cdot \frac{10}{3} = \frac{2}{35} \cdot \frac{10}{3} = \frac{4}{21}$ 5) $1\frac{31}{35} : (2 - \frac{8}{9} : 1\frac{19}{45}) = \frac{66}{35} : (2 - \frac{8}{9} : \frac{64}{45}) = \frac{66}{35} : (2 - \frac{8}{9} \cdot \frac{45}{64}) = \frac{66}{35} : (2 - \frac{5}{8}) = \frac{66}{35} : \frac{11}{8} = \frac{66}{35} \cdot \frac{8}{11} = \frac{48}{35} = 1\frac{13}{35}$ 6) $2\frac{7}{9} \cdot \frac{18}{25} + \frac{9}{60} : (\frac{7}{12} - \frac{3}{5}) = 2 + \frac{3}{20} : (\frac{35-36}{60}) = 2 + \frac{3}{20} : (-\frac{1}{60}) = 2 + \frac{3}{20} \cdot (-60) = 2 - 9 = -7$ 7) $(5\frac{1}{16} - 1\frac{1}{8}) (\frac{5}{6} + \frac{3}{14}) = (\frac{81}{16} - \frac{18}{16}) (\frac{35+9}{42}) = \frac{63}{16} \cdot \frac{44}{42} = \frac{3}{8} \cdot \frac{11}{1} = \frac{33}{8} = 4\frac{1}{8}$ 8) $(\frac{4}{5} + \frac{4}{7}) (3\frac{3}{8} + 2\frac{11}{4}) = \frac{48}{35} \cdot (3\frac{3}{8} + 4\frac{3}{4}) = \frac{48}{35} \cdot (3\frac{3}{8} + 4\frac{6}{8}) = \frac{48}{35} \cdot 8\frac{1}{8} = \frac{48}{35} \cdot \frac{65}{8} = \frac{6}{7} \cdot \frac{13}{1} = \frac{78}{7} = 11\frac{1}{7}$ 9) $(2\frac{13}{48} + 2\frac{5}{12}) : 3\frac{3}{4} - 9\frac{3}{4} : 12 = 4\frac{33}{48} : \frac{15}{4} - \frac{39}{4} : 12 = 4\frac{11}{16} \cdot \frac{4}{15} - \frac{13}{16} = \frac{75}{16} \cdot \frac{4}{15} - \frac{13}{16} = \frac{5}{4} - \frac{13}{16} = \frac{7}{16}$ 10) $-3\frac{1}{7} \cdot (-8) - 2,9 : 0,1 + \frac{11}{21} : (-3\frac{2}{3}) = \frac{22}{7} \cdot 8 - 29 + \frac{11}{21} \cdot (-\frac{3}{11}) = \frac{176}{7} - 29 - \frac{1}{7} = \frac{175}{7} - 29 = 25 - 29 = -4$ 11) $4\frac{1}{3} \cdot 5 + 2,4 : (-0,1) - \frac{14}{15} : 1\frac{2}{5} = \frac{65}{3} - 24 - \frac{14}{15} \cdot \frac{5}{7} = 21\frac{2}{3} - 24 - \frac{2}{3} = -3$ 12) $(6 - 2\frac{4}{5}) \cdot 3\frac{1}{8} - 1\frac{3}{5} : \frac{1}{4} = 3\frac{1}{5} \cdot \frac{25}{8} - \frac{8}{5} \cdot 4 = \frac{16}{5} \cdot \frac{25}{8} - \frac{32}{5} = 10 - 6,4 = 3,6$ 13) $3\frac{1}{7} \cdot (-4) - 1,8 : (-0,1) + \frac{20}{21} : 1\frac{2}{3} = -12\frac{4}{7} + 18 + \frac{20}{21} \cdot \frac{3}{5} = 5\frac{3}{7} + \frac{4}{7} = 6$ 14) $4\frac{1}{6} \cdot (1\frac{1}{2} - \frac{3}{5}) + (\frac{3}{4} + \frac{5}{6}) \cdot 6 = \frac{25}{6} \cdot \frac{9}{10} + (\frac{9+10}{12}) \cdot 6 = \frac{5}{2} \cdot \frac{3}{2} + \frac{19}{2} = 3,75 + 9,5 = 13,25$ 15) $\frac{7}{9} : 1\frac{1}{6} + 2,7 : (-0,1) - 4\frac{1}{3} \cdot (-4) = \frac{7}{9} \cdot \frac{6}{7} - 27 + \frac{52}{3} = \frac{2}{3} - 27 + 17\frac{1}{3} = 1 - 10 = -9$ 16) $7 \cdot 2\frac{6}{7} + \frac{53}{12} : (\frac{7}{9} - \frac{9}{4}) = 20 + \frac{53}{12} : (\frac{28-81}{36}) = 20 + \frac{53}{12} \cdot (-\frac{36}{53}) = 20 - 3 = 17$