Вычисли значение выражений: $(\frac{9}{16} + 2\frac{3}{8}) \cdot 4$

1) Давай решим: $(\frac{9}{16} + 2\frac{3}{8}) \cdot 4 = (\frac{9}{16} + \frac{19}{8}) \cdot 4 = (\frac{9}{16} + \frac{38}{16}) \cdot 4 = \frac{47}{16} \cdot 4 = \frac{47}{4} = 11\frac{3}{4} = 11,75$ 2) Решаем: $(\frac{4}{9} - 3\frac{1}{15}) \cdot 9 = (\frac{4}{9} - \frac{46}{15}) \cdot 9 = (\frac{20}{45} - \frac{138}{45}) \cdot 9 = -\frac{118}{45} \cdot 9 = -\frac{118}{5} = -23\frac{3}{5} = -23,6$ 3) Считаем: $(2\frac{3}{4} + 2\frac{1}{5}) \cdot 16 = (\frac{11}{4} + \frac{11}{5}) \cdot 16 = (\frac{55}{20} + \frac{44}{20}) \cdot 16 = \frac{99}{20} \cdot 16 = \frac{99 \cdot 4}{5} = \frac{396}{5} = 79\frac{1}{5} = 79,2$ 4) Считаем: $(1\frac{11}{16} - 3\frac{7}{8}) \cdot 4 = (\frac{27}{16} - \frac{31}{8}) \cdot 4 = (\frac{27}{16} - \frac{62}{16}) \cdot 4 = -\frac{35}{16} \cdot 4 = -\frac{35}{4} = -8\frac{3}{4} = -8,75$ 5) Считаем: $(1\frac{3}{4} + 2\frac{4}{5}) \cdot 30 = (\frac{7}{4} + \frac{14}{5}) \cdot 30 = (\frac{35}{20} + \frac{56}{20}) \cdot 30 = \frac{91}{20} \cdot 30 = \frac{91 \cdot 3}{2} = \frac{273}{2} = 136\frac{1}{2} = 136,5$ 6) Решаем: $(\frac{1}{13} - 2\frac{3}{4}) \cdot 26 = (\frac{1}{13} - \frac{11}{4}) \cdot 26 = (\frac{4}{52} - \frac{143}{52}) \cdot 26 = -\frac{139}{52} \cdot 26 = -\frac{139}{2} = -69\frac{1}{2} = -69,5$ 7) Считаем: $1\frac{8}{17} : (\frac{12}{17} + 2\frac{7}{11}) = \frac{25}{17} : (\frac{12}{17} + \frac{29}{11}) = \frac{25}{17} : (\frac{132}{187} + \frac{493}{187}) = \frac{25}{17} : \frac{625}{187} = \frac{25}{17} \cdot \frac{187}{625} = \frac{1}{1} \cdot \frac{11}{25} = \frac{11}{25} = 0,44$ 8) Решаем: $3\frac{4}{9} : (1\frac{5}{9} - \frac{4}{7}) = \frac{31}{9} : (\frac{14}{9} - \frac{4}{7}) = \frac{31}{9} : (\frac{98}{63} - \frac{36}{63}) = \frac{31}{9} : \frac{62}{63} = \frac{31}{9} \cdot \frac{63}{62} = \frac{1}{1} \cdot \frac{7}{2} = \frac{7}{2} = 3\frac{1}{2} = 3,5$ Надеюсь, теперь всё понятно!