Упр.612 Часть 1 ГДЗ Виленкин Жохов 6 класс (Математика)
а) 2/3 * 6/7 : 4/7;
б) 11/12 : 7/24 * 21/22;
в) 15/16 : 3/8 * 3/4;
г) 13/14 * 7/25 : 13/25;
д) 3 3/4 * (4 1/2 : 6 3/4);
е) (2 2/7 + 1 1/7) * 1 1/6;
а) $$\frac{2}{3}\cdot\frac{6}{7}:\frac{4}{7}=\frac{2}{3}\cdot\frac{6}{7}\cdot\frac{7}{4}=\frac{2\cdot 6}{3\cdot 4}=1.$$
б) $$\frac{11}{12}:\frac{7}{24}\cdot\frac{21}{22}=\frac{11}{12}\cdot\frac{24}{7}\cdot\frac{21}{22}=3.$$
в) $$\frac{15}{16}:\frac{3}{8}\cdot\frac{3}{4}=\frac{15}{16}\cdot\frac{8}{3}\cdot\frac{3}{4}=\frac{15}{8}=1\frac{7}{8}.$$
г) $$\frac{13}{14}\cdot\frac{7}{25}:\frac{13}{25}=\frac{13}{14}\cdot\frac{7}{25}\cdot\frac{25}{13}=\frac{1}{2}.$$
д) $$3\frac{3}{4}\cdot\left(4\frac{1}{2}:6\frac{3}{4}\right)=\frac{15}{4}\cdot\left(\frac{9}{2}:\frac{27}{4}\right)=\frac{15}{4}\cdot\frac{9}{2}\cdot\frac{4}{27}=\frac{5}{2}=2\frac{1}{2}.$$
е) $$\left(2\frac{2}{7}+1\frac{1}{7}\right)\cdot1\frac{1}{6}=3\frac{3}{7}\cdot1\frac{1}{6}=\frac{24}{7}\cdot\frac{7}{6}=4.$$
ж) $$\left(6\frac{1}{2}-4\frac{1}{4}\right):2\frac{1}{2}=\left(6\frac{2}{4}-4\frac{1}{4}\right):\frac{5}{2}=2\frac{1}{4}:\frac{5}{2}=\frac{9}{4}\cdot\frac{2}{5}=\frac{9}{10}.$$
з) $$\left(4\frac{8}{15}-1\frac{1}{3}\right)\cdot1\frac{7}{8}=\left(4\frac{8}{15}-1\frac{5}{15}\right)\cdot\frac{15}{8}=3\frac{3}{15}\cdot\frac{15}{8}=\frac{16}{5}\cdot\frac{15}{8}=6.$$
и) $$\left(2\frac{2}{3}+1\frac{5}{6}\right):1\frac{1}{2}=\left(2\frac{4}{6}+1\frac{5}{6}\right):\frac{3}{2}=3\frac{3}{6}:\frac{3}{2}=\frac{7}{2}:\frac{3}{2}=\frac{7}{3}.$$
к) $$\left(3\frac{1}{6}-2\frac{7}{15}\right):1\frac{2}{5}=\left(3\frac{5}{30}-2\frac{14}{30}\right):\frac{7}{5}=1\frac{21}{30}:\frac{7}{5}=\frac{7}{10}\cdot\frac{5}{7}=\frac{1}{2}.$$
л) $$\left(1\frac{2}{3}+2\frac{4}{9}\right):\left(4\frac{26}{27}-2\frac{2}{9}\right)=\left(1\frac{6}{9}+2\frac{4}{9}\right):\left(4\frac{26}{27}-2\frac{6}{27}\right)=3\frac{1}{9}:2\frac{20}{27}=\frac{28}{9}:\frac{74}{27}=\frac{28}{9}\cdot\frac{27}{74}=\frac{42}{37}.$$
м) $$\left(6\frac{1}{24}-\frac{2}{3}\right):\left(3\frac{1}{2}+1\frac{7}{8}\right)=\left(6\frac{1}{24}-\frac{16}{24}\right):\left(3\frac{4}{8}+1\frac{7}{8}\right)=5\frac{9}{24}:5\frac{3}{8}=\frac{43}{8}:\frac{43}{8}=1.$$
Ответ
а) 1; б) 3; в) $$1\frac{7}{8}$$; г) $$\frac{1}{2}$$; д) $$2\frac{1}{2}$$; е) 4; ж) $$\frac{9}{10}$$; з) 6; и) $$\frac{7}{3}$$; к) $$\frac{1}{2}$$; л) $$\frac{42}{37}$$; м) 1.
