258 Вправа 258Алгебра 8 клас Бевз 2025 · § 5 · стор. 54

258. Виконай дії.

а) ${\displaystyle (1\frac{8}{13}:3\frac{3}{13}+\frac{5}{7}:\frac{8}{21}):(8\frac{1}{8}+3\frac{1}{2})}$=

=${\displaystyle (\frac{21}{13}\cdot \frac{13}{42}+\frac{5}{7}\cdot \frac{21}{8}):11\frac{5}{8}=}$${\displaystyle (\frac{1}{2}+\frac{15}{8}):\frac{93}{8}}$=

=${\displaystyle \frac{19}{8}\cdot \frac{8}{93}=}$${\displaystyle \frac{19}{93}}$;

б) ${\displaystyle (28\frac{4}{5}:13\frac{5}{7}+6\frac{3}{5}:\frac{2}{3}):(1\frac{11}{16}:2\frac{1}{4})}$=

=${\displaystyle (\frac{144}{5}\cdot \frac{7}{96}+\frac{33}{5}\cdot \frac{3}{2}):(\frac{27}{16}\cdot \frac{4}{9})=}$${\displaystyle (2,1+9,9):\frac{3}{4}}$=

=${\displaystyle 12\cdot \frac{4}{3}=}$${\displaystyle 16}$.