$1,4.\dfrac{15}{49}-\Bigg(\dfrac{4}{5}+\dfrac{2}{3}\Bigg):2\dfrac{1}{5}\\=\dfrac{7}{5}.\dfrac{15}{49}-\Bigg(\dfrac{12}{15}+\dfrac{10}{15}\Bigg):\dfrac{11}{5}\\=\dfrac{3}{7}-\dfrac{22}{15}.\dfrac{5}{11}\\=\dfrac{3}{7}-\dfrac{2}{3}\\=\dfrac{9}{21}-\dfrac{14}{21}\\=\dfrac{-5}{21}\\\Bigg(-\dfrac{2}{3}+1\dfrac{1}{4}-\dfrac{1}{6}\Bigg).\dfrac{-24}{10}:0,5\\=\Bigg(-\dfrac{2}{3}+\dfrac{5}{4}-\dfrac{1}{6}\Bigg).\dfrac{-12}{5}:\dfrac{1}{2}\\=\Bigg(-\dfrac{-8}{12}+\dfrac{15}{12}-\dfrac{2}{12}\Bigg).\dfrac{-12}{5}.2\\=\dfrac{5}{12}.\dfrac{-24}{5}\\=-2$