Question

пж быстреееееееееееееее​

Answer 1

$1)\ \ \Big(8\dfrac{1}{42}-12\dfrac{4}{21}\Big)-\Big(5\dfrac{1}{42}-3\dfrac{3}{7}\Big)=8\dfrac{1}{42}-12\dfrac{8}{42}-5\dfrac{1}{42}+3\dfrac{18}{42}=\\\\\\=8-12-5+3+\dfrac{1}{42}-\dfrac{8}{42}-\dfrac{1}{42}+\dfrac{18}{42}=-6+\dfrac{10}{42}=-6+\dfrac{5}{21}=\\\\=\dfrac{-121}{21} =-5\dfrac{16}{21}$

$2)\ \ -19\dfrac{7}{16}-\Big(25\dfrac{5}{8}-28\dfrac{1}{2}\Big)-\dfrac{3}{4}=-19\dfrac{7}{16}-25\dfrac{10}{16}+28\dfrac{8}{16}-\dfrac{12}{16}=\\\\\\=-19-25+28-\dfrac{7}{16}-\dfrac{10}{16}+\dfrac{8}{16}-\dfrac{12}{16}=-16+\dfrac{-21}{16}=-16-1\dfrac{5}{16}=\\\\\\=-17\dfrac{5}{16}$