$\left(-\frac{2}{5}\right)\cdot(-1{,}25)-\left(0{,}3+\frac{7}{10}\right)\div0{,}2$

Question

$Фото задания: $\left(-\frac{2}{5}\right)\cdot(-1{,}25)-\left(0{,}3+\frac{7}{10}\right)\div0{,}2$$ Фото задания

Accepted Answer

Преобразуем десятичные дроби: $1{,}25=\frac{5}{4}$, $0{,}3=\frac{3}{10}$, $0{,}2=\frac{1}{5}$.

\[\left(-\frac{2}{5}\right)\cdot\left(-\frac{5}{4}\right)-\left(\frac{3}{10}+\frac{7}{10}\right)\div\frac{1}{5}\]

\[\frac{1}{2}-1\cdot5=\frac{1}{2}-5=-\frac{9}{2}\]

Ответ: $-\frac{9}{2}=-4\frac{1}{2}$.

\(\left(-\frac{2}{5}\right)\cdot(-1{,}25)-\left(0{,}3+\frac{7}{10}\right)\div0{,}2\)