Упр.553 ГДЗ Никольский Потапов 6 класс (Математика)
а) -33/80+(3/16-39/80);
б) 2/45+(-3/45+7/9);
в) 7/15-(4/15-1/5);
г) -5/16-(1/16-7/8);
д) -1/27+(7/9-2/3);
е) (-2/15-4/5)+3/10;
ж) (-2/15+4/5)-3/10;
з) -(5/8-5/12)+1/24.
а) $$-\frac{33}{80}+\left(\frac{3}{16}-\frac{39}{80}\right)=\left(-\frac{33}{80}-\frac{39}{80}\right)+\frac{3}{16}=-\frac{72}{80}+\frac{15}{80}=-\frac{57}{80}$$
б) $$\frac{2}{45}+\left(-\frac{3}{45}+\frac{7}{9}\right)=\left(\frac{2}{45}-\frac{3}{45}\right)+\frac{7}{9}=-\frac{1}{45}+\frac{35}{45}=\frac{34}{45}$$
в) $$\frac{7}{15}-\left(\frac{4}{15}-\frac{1}{5}\right)=\left(\frac{7}{15}-\frac{4}{15}\right)+\frac{1}{5}=\frac{3}{15}+\frac{1}{5}=\frac{1}{5}+\frac{1}{5}=\frac{2}{5}$$
г) $$-\frac{5}{16}-\left(\frac{1}{16}-\frac{7}{8}\right)=\left(-\frac{5}{16}-\frac{1}{16}\right)+\frac{7}{8}=-\frac{6}{16}+\frac{14}{16}=\frac{8}{16}=\frac{1}{2}$$
д) $$-\frac{1}{27}+\left(\frac{7}{9}-\frac{2}{3}\right)=-\frac{1}{27}+\frac{7}{9}-\frac{2}{3}=\frac{-1+21-18}{27}=\frac{2}{27}$$
е) $$\left(-\frac{2}{15}-\frac{4}{5}\right)+\frac{3}{10}=-\frac{2}{15}-\frac{4}{5}+\frac{3}{10}=\frac{-4-24+9}{30}=-\frac{19}{30}$$
ж) $$\left(-\frac{2}{15}+\frac{4}{5}\right)-\frac{3}{10}=-\frac{2}{15}+\frac{4}{5}-\frac{3}{10}=\frac{-4+24-9}{30}=\frac{11}{30}$$
з) $$-\left(\frac{5}{8}-\frac{5}{12}\right)+\frac{1}{24}=-\frac{5}{8}+\frac{5}{12}+\frac{1}{24}=\frac{-15+10+1}{24}=-\frac{4}{24}=-\frac{1}{6}$$
Ответ
а) $$-\frac{57}{80}$$; б) $$\frac{34}{45}$$; в) $$\frac{2}{5}$$; г) $$\frac{1}{2}$$; д) $$\frac{2}{27}$$; е) $$-\frac{19}{30}$$; ж) $$\frac{11}{30}$$; з) $$-\frac{1}{6}$$.
