22. Вычислите: а) $(\frac{4}{9}+\frac{5}{12})\cdot\frac{18}{31}$; б) $\frac{6}{25}\cdot(\frac{11}{15}-\frac{9}{20})$; в) $(4-3\frac{7}{15})\cdot\frac{5}{8}$; г) $(1\frac{1}{24}-\frac{5}{12})\cdot4\frac{1}{8}$.

Question

$Фото задания: 22. Вычислите: а) $(\frac{4}{9}+\frac{5}{12})\cdot\frac{18}{31}$; б) $\frac{6}{25}\cdot(\frac{11}{15}-\frac{9}{20})$;…$ Фото задания

Accepted Answer

$\left(\frac{4}{9}+\frac{5}{12}\right)\cdot\frac{18}{31}=\left(\frac{16}{36}+\frac{15}{36}\right)\cdot\frac{18}{31}=\frac{31}{36}\cdot\frac{18}{31}=\frac12$.
$\frac{6}{25}\cdot\left(\frac{11}{15}-\frac{9}{20}\right)=\frac{6}{25}\cdot\left(\frac{44}{60}-\frac{27}{60}\right)=\frac{6}{25}\cdot\frac{17}{60}=\frac{17}{250}$.
$\left(4-3\frac{7}{15}\right)\cdot\frac58=\left(4-\frac{52}{15}\right)\cdot\frac58=\frac{8}{15}\cdot\frac58=\frac13$.
$\left(1\frac{1}{24}-\frac5{12}\right)\cdot4\frac18=\left(\frac{25}{24}-\frac{10}{24}\right)\cdot\frac{33}{8}=\frac{15}{24}\cdot\frac{33}{8}=\frac{165}{64}=2\frac{37}{64}$.

Ответ: а) $\frac12$; б) $\frac{17}{250}$; в) $\frac13$; г) $2\frac{37}{64}$.

22. Вычислите: а) \((\frac{4}{9}+\frac{5}{12})\cdot\frac{18}{31}\); б) \(\frac{6}{25}\cdot(\frac{11}{15}-\frac{9}{20})\); в) \((4-3\frac{7}{15})\cdot\frac{5}{8}\); г) \((1\frac{1}{24}-\frac{5}{12})\cdot4\frac{1}{8}\).